JPH0451083B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a lumped constant electromagnetic delay line that combines an inductance element and a capacitor, and more particularly to an electromagnetic delay line that has a fast rise time and little output waveform distortion.

[Prior art and its problems]

Conventionally, lumped constant electromagnetic delay lines have been created by winding a conductor around a bobbin to form an inductance element.
It is known that a capacitor is connected between a conducting wire and the ground at each predetermined turn of the inductance element, and the inductance element has a configuration consisting of a plurality of sections.

However, in the electromagnetic delay line configured in this manner, it is difficult to select the optimum polarity and value of the coupling coefficient between sections in the inductance element in a high frequency band. In particular, it is difficult to select the optimum values of the coupling coefficients for adjacent sections and for the coupling coefficients for adjacent sections.

As a result, the rise time is as fast as 1 ns,
Moreover, it was difficult to obtain an output waveform with good distortion.

[Purpose of the invention]

The present invention has been made to solve these conventional drawbacks, and its object is to provide an electromagnetic delay line with an extremely fast rise time, low output waveform distortion, and good delay characteristics.

[Structure and effects of the invention]

To achieve this purpose, a capacitor is connected between the ground and the center of each conductor that intersects with the virtual axis of the folded conductor to form an electromagnetic delay line consisting of multiple sections. At the same time, both sides of the center portion of each of the conductive wires are deformed in opposite directions so that the conductive wire has one turn or more.

According to the configuration of the present invention, it becomes possible to easily select and adjust the optimum coupling state in the inductance element in a high frequency band, thereby achieving ultra-high speed rise time and distortion of the output waveform. It is possible to improve the delay characteristics.

[Embodiments of the invention]

The details of the present invention will be explained below.

FIG. 1 is a developed view showing an embodiment of the electromagnetic delay line of the present invention.

In the figure, a folded conductive line 1 having a rectangular folded shape and constituting an inductance element includes:
A capacitor C is connected between each central part of the conductor 2 perpendicular to the virtual axis (horizontal virtual line in the figure, not shown) and the ground, forming a lumped constant electromagnetic delay line having multiple sections. There is.

This folded conductor line 1 has a pitch P per section, that is, 1
The length X between the conductor wires 2 in the section is shorter, and the center part of the conductor wire 2 to which the capacitor C is connected is slightly parallel to the imaginary axis and bent into a crank shape, and towards the end it is perpendicular to the imaginary axis. It extends in the direction of

The unfolded folded conductor line 1 connects the conductor line 2 of the adjacent section with the imaginary lines M-M, N-N, Q-Q, and R-R drawn in parallel to the imaginary axis in the middle of the conductor line 2 in each section. The ends of each are bent at right angles in opposite directions to form the shape shown in FIG. That is, the conductive wires 2 in adjacent sections are arranged so that the conductive wires 2 in adjacent sections face each other on the same plane with an interval between them on a bobbin having a rectangular cross section. In FIG. 2, capacitor C is omitted.

FIG. 3 shows an equivalent circuit diagram of the electromagnetic delay line of the present invention, and symbols S0, S1, and S2 in the figure indicate sections on the right side in sequence with respect to the section on the left side in FIG. The symbol _a1 is the coupling coefficient between the section S1 adjacent to the right side of the section S0, and the symbol _a2 is the coupling coefficient between the section S1 and the section S1 adjacent to the right side of the section S0.
It shows the coupling coefficient between 0 and the section S2 to be coupled by one on the right side.

Note that FIG. 4A is a side view of one section of the conductor 2 of the folded conducting path 1 shown in FIG. 2, viewed from the side.

Next, we will discuss the coupling coefficient in the electromagnetic delay line configured in this way.

Generally, when considering the coupling coefficient in the folded conductor line 1, there are coupling coefficients between all the conductors forming the folded conductor line 1 whose angles are not right angles, but among them, the one with the largest value is considered. By doing so, it is possible to know the tendency of the coupling coefficient of the folded conducting line 1.

Therefore, the electromagnetic delay line of the present invention has a conductive wire 2 parallel to the Z direction in FIGS. 2 and 4 described above.
Since the connection between the two will have the greatest influence,
I'll consider it.

When radio waves flow in the direction of the arrows shown in FIGS. 1 and 2 in the folded conductor path 1, the sections S0,
Between S1, that is, regarding the coupling coefficient _a1 , A-B,
D-E, F-G, and H-I are related, and the current direction is the same between A-B and H-I and between D-E and F-G, and the coupling is positive. , between F and G and D
-E and H-I are in opposite directions, resulting in a negative coupling.

The total value of those coupling coefficients is greatly influenced by the positive coupling between DE and FG, which are closest to each other, so that the coupling coefficient between sections S0 and S1 is positive.

On the other hand, regarding the coupling coefficient _a2 between sections S0 and S2, A-B, DE and J-K, T-U are related, but the direction of the current is between A-B, J-K and D. −
The directions between E and TU are the same, resulting in a positive coupling, and the directions between A-B and TU and between D-E and J-K are opposite, resulting in a negative coupling.

Therefore, the negative coupling between DE and JK, which are closest to each other, has a large influence on the total value, and the coupling between sections S0 and S2 becomes negative.

Similarly, regarding the coupling coefficient a _o , if we consider only the conductor 2 parallel to the Z direction in Fig. 2, the odd-numbered coupling coefficient will be positive for the same reason as mentioned above, and the even-numbered one will be positive. The coupling coefficient of becomes negative.

When examining the delay characteristics of the electromagnetic delay line of the present invention in detail, it is necessary to calculate the coupling coefficients a ₁ , a ₂ , and a _o by taking into account the coupling of other conductor parts in addition to the coupling described above. However, in the electromagnetic delay line of the present invention, odd-numbered coupling coefficients tend to be positive and even-numbered coupling coefficients tend to be negative, which is a desirable configuration for an electromagnetic delay line.

In general, in electromagnetic delay lines, the coupling coefficients a ₁ and a ₂ have a large influence on the delay characteristics, and according to the present invention, it is easy to set the polarities of the coupling coefficients a ₁ and a ₂ to desired polarities. , pitch P, conductor 2 for one section
The value of the coupling coefficient can be optimized by appropriately selecting the length X between the two and the overlapping and opposing length.

In the present invention, the folded conductive line 1 can be easily formed by fetetching a copper foil or a copper plate, or can be formed by bending a conductive wire having a circular cross section.

In the above embodiment, the folded conductor line 1 has an air-core free-standing structure, but a copper foil with a thin insulating film pasted thereon is formed by photo-etching or the like, and is wound together with the insulating film around a rectangular bobbin or the like. It is also possible.

In addition to the case where the folded conductor line 1 is constructed by bending the conductor 2 twice in one section as shown in FIG. 4A, the folded conductor line 1 may be constructed by increasing the number of bends to three times as shown in FIG. 4B. It is also possible to bend the coil eight times as shown in FIG.

Furthermore, the length of the bending can be arbitrarily selected according to the desired characteristics. For example, as shown in _FIG . It is also possible to make the length of the bent portion in the longitudinal direction different from the length Y.

As a specific example, the present inventor has provided a diameter of 0.1 mm.
Using conductor wire, pitch P = 1mm, X = 0.95mm,
The dimensional relationship is Z = 1.6 mm, Y = 4 mm, Y ₁ = 3.1 mm, that is, the dimensional relationship is not flat in the horizontal direction as shown in Figure 4B, but the dimensions in the Y direction and Y ₁ direction are larger than in the Z direction. Therefore, we experimented with a long dimension relationship in the vertical direction.

Then, the coupling coefficient in the inductance element is
a ₁ = 0.13, coupling coefficient a ₂ = -0.15, coupling coefficient a ₃ =
0.006, and when combined with a capacitor of 2pF to form a 20-section electromagnetic delay line, the total delay time is
We were able to obtain an ultrahigh-speed electromagnetic delay line with a characteristic impedance of 5ns, a characteristic impedance of 50Ω, and an output pulse rise time of approximately 950ps.

FIG. 5 is a developed view showing another embodiment of the present invention, and FIG. 6 is a side view thereof.

In the electromagnetic delay line in this embodiment, the conductor 2 including the part connecting the capacitor C has a straight shape perpendicular to the imaginary axis, and the imaginary lines M-M, N
The distance Y ₂ between the imaginary lines Q-Q and R-R is made narrower than the distance Y ₃ between -N, and the conductor 2 is bent along these imaginary lines so that the conductors 2 in adjacent sections do not touch each other. It is what it is.

According to such a configuration, the shape of the conducting wire 2 is simplified and the conducting wires 2 in adjacent sections overlap each other, so that the coupling coefficient increases, and especially the coupling coefficient a ₁
It becomes easy to increase the value of .

FIG. 7 is a developed view showing another embodiment of the present invention, in which, contrary to the folded conductor line 1 shown in FIG. It is something.

With the electromagnetic delay line configured in this way, it is possible to reduce the distance between conductors D-E and J-K, where the direction of current is opposite in the interval between two conductors and the conductors J-K are negatively coupled. It is possible to increase the coupling coefficient a ₂ of the section in which the data is stored, that is, the value of the negative coupling between the sections S0 and S2.

Further, FIG. 8 is a partial plan view showing another embodiment of the electromagnetic delay line of the present invention, showing only two portions of the conducting wire intersecting the virtual axis.

The electromagnetic delay line with this configuration has conductor wires 2 that intersect diagonally with respect to the virtual axis, and the electromagnetic delay line is constructed using a folded conductor path 1 such that when bent, adjacent conductor wires 2 become parallel to each other. It is composed of

According to this configuration, the length at which positive coupling is formed by currents flowing in the same direction in adjacent sections becomes longer, and on the other hand, the coupling is reduced because the conductor wires 2 through which currents flow in opposite directions have an angle. I will do it.

Therefore, in particular, the value of the coupling coefficient a ₁ can be selected to be large.

FIGS. 9 and 10 are a developed view and a side view showing still another embodiment of the electromagnetic delay line of the present invention, in which the interval between the conductive wires 2 in one section is formed alternately into wide parts and narrow parts. This is what happens. In other words, this configuration uses both the structure shown in FIG. 5 that increases the coupling coefficient a ₁ and the structure shown in FIG. 7 that increases the coupling coefficient a ₂ .

That is, in the part marked Z between the imaginary lines N-N and Q-Q, the negative coupling part due to the reverse current approaches in coupling with the one interval apart, and the degree of coupling is increased, Virtual lines M-M and R-R
The end portions of each are bent to overlap and approach each other, increasing the positive coupling coefficient a ₁ due to the same direction current in the adjacent sections.

Therefore, by adjusting the interval and length of the wide and narrow portions of the conducting wire 2 in these one section, it becomes easier to adjust the values of the coupling coefficients a ₁ and a ₂ to optimal values.

In each of the above-mentioned embodiments, the folded conductor line 1 is arranged so that the conductor line 2 has a rectangular cross section when viewed from the side.
However, in the present invention, the conductor 2 is not limited to a rectangular cross section, but can be deformed so that the ends thereof overlap, that is, one turn or more when viewed from the side, to have a triangular, pentagonal, or triangular cross section. It may be formed into various shapes such as a circle.

As explained above, in the electromagnetic delay line of the present invention, both sides of the central part of each conductor are deformed in opposite directions so that the conductor of the folded conductor line has one turn or more. By appropriately selecting the coupling by , it becomes easy to select the polarity and value of the coupling coefficient in the desired direction.

Therefore, in the ultra-high frequency band, the rise is extremely fast, output waveform distortion can be suppressed to a small level, and delay characteristics are improved.

[Brief explanation of the drawing]

Fig. 1 is a developed view showing an embodiment of the electromagnetic delay line of the present invention, Fig. 2 is an assembled perspective view of the inductance element shown in Fig. 1, and Fig. 3 is an equivalent circuit of the electromagnetic delay line shown in Fig. 1. 4 is a side view of the electromagnetic delay line of the present invention as seen from the side, FIGS. 5 and 6 are developed views and side views showing other embodiments of the present invention, and FIG.
8 and 8 are developed views and partial plan views showing other embodiments of the present invention, respectively, and FIGS. 9 and 10 are developed views and side views showing still other embodiments of the present invention. 1...Return conductor line, 2...Conductor wire, a ₁ , a ₂ ,
...a _o ...Coupling coefficient, C...Capacitor, S0, S
1, S2... section.

Claims (1)

[Scope of Claims] 1. An electromagnetic delay line consisting of a plurality of sections is constructed by connecting a capacitor between the center portion of each conductor that intersects with the virtual axis of the folded conductor and the ground among the conductors forming the folded conductor. In addition, an electromagnetic delay line characterized in that both sides of the central portion of each of the conductive wires are deformed in opposite directions so that the conductive wire has one turn or more. 2. The electromagnetic delay line according to claim 1, wherein the conductive wires are orthogonal to the virtual axis, and the distance between the conductive wires for one section is narrower than the distance between the center portions of adjacent conductive wires. 3. The electromagnetic delay line according to claim 1, wherein the conductive wires are perpendicular to the virtual axis, and the distance between the conductive wires for one section is wider than the distance between the center portions of adjacent conductive wires. 4. The electromagnetic delay line according to claim 1, wherein the conducting wire is formed obliquely with respect to a virtual axis. 5. The electromagnetic delay line according to claim 1, wherein the conducting wires are orthogonal to the virtual axis, and the intervals between the conducting wires in one section are alternately wide and narrow.