JPS63209309A - Microwave semiconductor device - Google Patents

Abstract

PURPOSE:To improve the detection sensitivity by adopting the constitution that ground conductors of a coplaner line are connected via a termination resistor so as to reduce the reflection of a sampling pulse passing through a diode and propagating through the coplaner line. CONSTITUTION:The ground conductors 20a, 20b of the coplaner line 3 are connected via a termination resistor 19. A sampling pulse propagated on the line 3 in the even number mode causes a potential difference between the ground conductors 20a, 20b, the potential difference is absorbed by the termination resistor 19 and diodes 8a, 8b are not switched in an undesired time. On the other hand, since the signal wave propagates on the line 3 in the odd number mode and no potential difference is caused between the ground conductors 20a, 20b of the line, no current flows to the resistor 19. Thus, the signal wave is applied to the diodes 8a, 8b without being attenuated by the termination resistor 19.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a microwave semiconductor device, and in particular to a microwave signal that is sampled by a pulse wave having a repetition frequency sufficiently lower than the signal frequency in the microwave band. The present invention relates to a microwave semiconductor device that performs phase detection or multiplication/mixing operation.

[Conventional technology]

In this type of microwave integrated circuit devices, double-plane circuits that use the back and front sides of a dielectric substrate are often used to widen the bandwidth and make the device smaller. Figure 6 shows, for example,
923 is an overall circuit diagram showing an example of a conventional device of this type, in which 1 is a dielectric substrate;
2 and 4 are microstrip lines, 3 is a coplanar line, and 15 is a slot/throat line, and the broken line shows the arrangement on the back side.

In FIG. 6, the conventional microwave semiconductor device includes first and second microstrip lines 2, which are provided on the back surface of a dielectric substrate 1 and which propagate sampling pulses and microwave signals applied to a terminal 5.6. 4, a coplanar line 3 provided on the surface of the dielectric substrate 1 and coupled to the second microstrip line 4, and a coplanar line 3 provided on the surface of the dielectric substrate 1 and coupled to the first microstrip line 2. a slot line 15 coupled to the coplanar line 3, and a slot line 15 connected to the coplanar line 3;
and a diode 8 provided at the junction of the coplanar line 3
a, 8b and capacitor 11a.

A pair of series circuits 10a, 10b formed by diodes 13a, 8b and capacitors 11a, 11b.
Output lines 12a, 1 are connected to each connection point with lb via a resistor 13.
2b, and an output terminal 14 connected to the middle point of the resistor 13, and an inductor 17 whose one end is connected to the second microstrip line 4 and the other end is grounded by a conductive through ball 18. It consists of The slot line 15 has a first slot line 15a and a second slot line 15b centered at the cross-coupling point with the first microstrip line 2, and the second slot line FI! A terminating resistor 7 is connected to r15b.

Next, we will explain the case where this microwave semiconductor device is operated as a sampling phase detector that detects the phase difference between the above-mentioned microwave input signal and a reference signal having a frequency that is an integer fraction of the frequency of the microwave input signal. do.

A sampling pulse having the same repetition frequency as the reference signal generated by a pulse generator using a Stenbri force Halli diode is applied to terminal 5 and propagated through the first microstrip line 2, resulting in microstrip-to-slot line conversion. The microstrip line 2 is connected by the device 16.
It is distributed to slot lines isa and 15b which are cross-coupled with the slot lines isa and 15b. The sampling pulse propagating to the second slot line 15b is absorbed by the terminating resistor 7, and no unnecessary reflection occurs. The remaining sampling pulses propagating through the first slot line 15a are applied to diodes 8a and 8b provided at the junction between the first slot line 15a and the coplanar line 3, and the remaining sampling pulses are applied to the diodes 8a and 8b provided at the junction between the first slot line 15a and the coplanar line 3.

8b is made conductive (ON state). When there is no sampling pulse, the diodes 8a and 8b are in an open state (OFF state). This open diode 8a
, 8b will be switched by the sampling pulse.

On the other hand, when a signal wave having a frequency that is an integral multiple of the repetition frequency of the sampling pulse is applied to the terminal 6, it propagates through the microstrip line 4, and is converted into an odd mode of the coplanar line 3 by the microstrip coplanar line converter 9. It is converted and propagates through the coplanar line 3 in an odd mode. Therefore, as a result, the sampling pulse passes through the diode 8a,
8b (when the diode is in the ON state), the voltage of the signal wave is applied to the capacitors Ila and llb. The voltage between the terminals of the capacitors lla and Ilb is taken out through output lines 12a and 12b, and from a terminal 14 connected to approximately the midpoint of the resistor 13.

Since this signal frequency is an integral multiple of the repetition frequency of the sampling pulse, the signal wave and the sampling pulse are synchronized. Therefore, the voltage appearing at terminal 14 is
After smoothing, it is obtained as a DC voltage corresponding to the phase difference between the two, which means that phase detection has been performed.

[Problem that the invention seeks to solve]

This conventional microwave semiconductor device operates as a sampling phase detector as described above, but part of the sampling pulse for switching the diodes passes through the diodes 8a and 8b and propagates through the coplanar line 3. This sampling pulse propagates through the coplanar line 3 in an even mode and is reflected by the microstrip-to-coplanar line converter 9, and this reflected sampling pulse is applied again to the diode, and the time required for a round trip from the normal time to the reflection point is Since the diode is switched at a time delayed by a certain amount of time, there is a drawback that the detection sensitivity of the phase detector decreases or malfunction occurs.

This invention was made in order to solve the above-mentioned problems, and provides a microwave semiconductor device that can reduce the reflection of the sampling pulse that passes through the diode and propagates on the coplanar line, and improves the detection sensitivity. The purpose is to provide.

[Means for solving problems]

The microwave semiconductor device according to the present invention has a resistor connected between both ground conductors of a coplanar line.

[Effect]

In this invention, the resistor connecting between the ground conductors of the coplanar line absorbs only the sampling pulse propagating on the coplanar line and does not absorb the microwave signal propagating on the coplanar line, so the microwave signal is sampled without attenuating it. By reducing pulse reflection, when operating as a sampling phase detector, detection sensitivity decrease and malfunction can be reduced.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 shows an overall circuit diagram of a microwave semiconductor device according to an embodiment of the present invention.

In FIG. 1, the microwave semiconductor device of this example is as follows:
In addition to the configuration of the conventional device, the ground conductor 208 of the coplanar line 3
．． 20b are connected via a terminating resistor 19.

Next, a case will be described in which the device of this embodiment is operated as a sampling phase detector. Here, the operation of propagating the signal wave to the diodes is the same as the operation of the conventional device shown in FIG. 6, and the mode of propagation 111i of the sampling pulse from the slot line 15 to the diodes 3a and 8b will be described.

Figure 2 shows a slot-node line 15a to which a diode is installed.
FIG. 3 is a diagram for explaining a joint between the line and the coplanar line 3 and a main part of the coplanar line 3.

The junction between the first slot line 15a and the coplanar line 3 is a T-branch as shown in FIG. The electric field of the sampling pulse is distributed as shown by the arrows in the figure and applied to both diodes 8a and 8b, so if the T-branch is symmetrical, the phase of the electric field applied to both diodes 8a and 8b is the same, and the diode The sampling pulses passing through without being combined with 8a and 8b excites the coplanar line 3 in an even mode. The sampling pulse propagating through the coplanar line 3 in an even mode generates a potential difference between the ground conductors 20a and 20b, but this potential difference is absorbed by the terminating resistor 19. Therefore, the diode 8a.

8b is not switched at unnecessary times. On the other hand, since the signal wave propagates through the coplanar line 3 in an odd mode with an electric field indicated by the broken line arrow in the figure, the resistor 19 has a No current flows.

Therefore, the signal wave is applied to the diodes 13a and 8b without being attenuated by the terminating resistor 19.

In the above embodiment, the line after the terminating resistor 7 of the invalid slot line 15b is constructed with slotted grooves having the same dimension and width, but in order to achieve a termination with less reflection, the line is shown in FIG. 3. As shown, the structure may be such that the width is widened at the terminal resistor 7 and higher.

Further, in the above embodiment, a pair of series circuits 10a and 10b consisting of a diode and a capacitor and a terminating resistor 7.19
is provided on the same side as the coplanar line 3 and the slot line 5 and directly connected to these ground conductors. However, as shown in FIG.
, 18e, 18f, and 18g, the series circuit 10a is provided on the back surface of the coplanar line 3 and the slot line 15.

10b, the terminating resistor 7.19 may be connected to the ground conductor.

In this case, all components such as diodes, capacitors, resistors, and inductors are mounted on only one side of the dielectric substrate, which has the advantage of simplifying work and reducing manufacturing costs.

Further, in the above embodiment, the number of terminating resistors 19 is one, but the present invention is not limited to this, and as shown in FIG. 5, two or more terminating resistors may be used.

Further, in the above embodiment, a case has been described in which it operates as a sampling phase detector, but as described above, it may also operate as a frequency multiplication mixer, and the same effects as in the above embodiment can be obtained.

〔Effect of the invention〕

As described above, according to the present invention, the ground conductors of the coplanar line are connected via the terminating resistor to absorb sampling pulses that pass through the diode and propagate on the coplanar line. This prevents the signal from being switched by unnecessary reflected waves of the sampling pulse, and provides high detection sensitivity as a phase detector.
As a multiplication frequency mixer, it has the effect of obtaining high efficiency.

[Brief explanation of the drawing]

FIG. 1 is an overall circuit diagram of an embodiment of the microwave semiconductor device according to the present invention, FIG. 2 is an explanatory diagram of the main part of the joint between the coplanar line and the slot line of the above embodiment, and FIG. 3 is the present invention. FIG. 4 and FIG. 5 are diagrams showing a part of still other embodiments of the present invention, and FIG. 6 is an overall circuit diagram of a conventional microwave semiconductor device. be. 1... Dielectric, 2.4... 1st. Second microstrip line, 3... Coplanar line, 5,6.14.
・Terminal, 7.19 ・Terminal resistor, 10a, 10b・
...Series circuit, 8a, 8b...Diode, 9...
Microstrip coplanar line converter, lla, 1
1b... Capacitor, 15... Slot line, 16
... Microstrip slot line converter, 1.
8a-18h-Through hole for conduction, 20a, 20b・
...Ground conductor. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (2)

[Claims] (1) First and second microstrip lines, slot lines, and coplanar lines provided on a dielectric substrate for a microwave integrated circuit, and the first microstrip line provided on both sides of the dielectric substrate. A microwave semiconductor device comprising: a slot line that is cross-coupled and connected to the coplanar line; and a pair of series circuits that are provided at the junction of the slot line and the coplanar line and are formed by connecting a diode and a capacitor in series. A microwave semiconductor device, characterized in that the two ground conductors of the coplanar line are connected at a required position of the coplanar line by one or more resistors. (2) A resistor connecting the pair of series circuits and both ground conductors of the coplanar line is provided on the surface of the dielectric substrate where the microstrip line is formed, and both ends of each resistor are connected to the dielectric substrate. 2. The microwave semiconductor device according to claim 1, wherein the microwave semiconductor device is connected to the conductor of the slot line and the coplanar line through a required number of conductive through holes formed in the slot line.