KR20010044423A - NRD Guide Frequency Converter - Google Patents

Abstract

PURPOSE: A frequency converter for an NRD guide is provided to use a non-radiative dielectric waveguide line which ensures low loss and little radiation in a discontinuity with a curve. CONSTITUTION: A local oscillation wave is applied from the outside and transferred to a circulator through an isolator. Any air cavity is not generated between a module of the circulator and an up-converter. A signal of an intermediate frequency inputted through the up-converter is mixed. The mixed signal is transferred to an output module of the circulator. A high mixed signal passes through a band type high pass filter and is radiated through an antenna(19). A low mixed signal in a low band is reflected, transferred to the isolator and absorbed in a terminator(7). An interval between an upper conductive plate and a lower conductive plate in a 50GHz band is 2.7mm. Therefore, a height of the NRD guide line is 2.7mm and a width of the NRD guide line is 3.0mm.

Description

NDR Guide Frequency Converter {NRD Guide Frequency Converter}

<67> The present invention relates to a frequency converter using a non-radial dielectric waveguide (NRD) guide line characterized by low loss, as well as almost no radiation in curves and discontinuities.

In the millimeter wave band, there is a great difficulty in design and implementation based on the same technology as the conventional MMIC of the frequency converter. Of course, there is also a difficulty in mounting a semiconductor device that is difficult in a general dielectric line. NRD guide technology has been introduced for the circuit configuration in the millimeter wave band, and recently, development of circuit elements such as millimeter wave band oscillator, modulator, mixer, etc. using the NRD guide technology has been made.

<69> The NRD guide should maintain the upper and lower conductor plates at intervals less than half the wavelength of the intended frequency, and configure the NRD guide circuit between the upper and lower conductor plates.

<70> The present invention introduces an NRD guide technology for overcoming the difficulties of existing technologies such as MMIC in the millimeter wave band, and provides an NRD guide line, a gun diode, an isolator, a circulator, an up-converter, a high pass filter, A frequency converter consisting of a combination of antennas.

<71> The first frequency converter of the present invention applies a local oscillation wave from the outside and transmits it to the circulator through the isolator, and mixes the local oscillation wave and the signal of the intermediate frequency input through the up-converter with no air gap. It transmits the mixed signal to the output terminal of, and in the linear high pass filter, the high frequency mixed signal passes through and radiates through the antenna. It is configured so as not to give.

The second frequency converter of the present invention is configured such that a gap exists between the up-converter and the circulator of the first frequency converter.

<73> The third frequency converter of the present invention generates a local oscillation wave from a gun diode mount equipped with a gun diode therein, applies a local oscillation wave to an NRD guide using a strip resonator, and transmits the oscillation wave to an circulator through an isolator. By mixing the local oscillation wave and the signal of intermediate frequency input through the up-converter with no air gap, the mixed signal is transmitted to the output terminal of the circulator, and the high frequency mixed signal from the linear high pass filter passes and radiates through the antenna. The low frequency mixed signal is reflected and transmitted to the isolator, absorbed by the terminator, so as not to affect the local oscillation unit, thereby forming a frequency converter.

The fourth frequency converter of the present invention is configured such that a gap exists between the up-converter and the circulator of the third frequency converter.

<75> In order to reduce the structure of the linear high pass filter of the first, second, third and fourth frequency converters of the present invention, a bend type high pass filter is configured.

<1> Fig. 1: A perspective view of a frequency converter capable of receiving a local oscillation wave from the outside.

2 is a plan view of a frequency converter capable of receiving a local oscillation wave from the outside.

3 is a block diagram of a frequency converter of the present invention.

4 is a perspective view of a circulator composed of a mode compressor and a ferrite resonator.

Fig. 5: Schematic diagram showing the role of the isolator in the frequency converter of the isolator equipped with an antireflective terminal at a specific terminal of the circulator.

6 is a perspective view of a ferrite resonator used in a circulator and an isolator.

<7> Fig. 7: Internal projected perspective view of the mode localized oscillator, the isolator, and the mode sprayer mounted on the circulator.

<8> Fig. 8: Internal perspective view of an antireflective terminal mounted on one terminal of the isolator.

Fig. 9: Graph shown in the network analyzer for insertion loss of the circulator and the isolator.

10: Graph shown in the network analyzer for the blocking properties of the circulator and the isolator.

Fig. 11: Measurement graph of the transmission loss of the LSM mode and the LSE mode when the NRD guide line of the mode compressor of FIG. 7 is mounted.

<12> FIG. 12: VSWR (voltage standing wave ratio) measurement graph of the antireflection terminal of FIG.

13 is a perspective view of an up-converter without voids.

14 is a plan view showing the schematic diagram of the incident (f _LO ) and the reflected (f _LO ± f _IF ) of the radio waves to the up-converter without voids.

15 is a cross-sectional view showing a schematic diagram of the incident (f _LO ) and the reflected (f _LO ± f _IF ) of the radio waves to an up-converter in which no void exists.

<16> FIG. 16: Top view of the Schottky diode mount mounted to an up-converter.

17 is a circuit diagram for supplying an IF and a bias voltage to an up-converter equipped with a Schottky diode mount.

Fig. 18 is a graph of measurement of VSWR (voltage standing wave ratio) according to the frequency of an up-converter in which no air gap exists.

19 is a perspective view of an up-converter in which voids are present.

<20> Figure 20: up to voids are present - a plan view showing a schematic view of the incidence of the radio waves to the converter (f _LO), reflection (f _LO ± f _IF).

Fig. 21 is a cross-sectional view showing a schematic diagram of an incident (f _LO ) and a reflection (f _LO ± f _IF ) of radio waves to an up-converter in which voids exist.

22 is a graph of measurement of VSWR (voltage standing wave ratio) according to the frequency of an up-converter in which voids exist.

23: Measurement graph of VSWR versus frequency for an up-converter with voids when the output of local oscillation is 7 dB and a bias current of 3 mA is supplied.

Fig. 24: In the two cases where the local oscillation frequency is 50 GHz and the outputs are 0 dBm and 7 dBm, the output of IF (Intermediated Frequency) is 7 dBm, and the conversion loss for the IF is changed. Measurement graph.

<25> FIG. 25: RF according to IF output when the local oscillation frequency is 50 GHz and the output is 0 dBm and 7 dBm, and the bias frequency is 3 mA and the RF frequency is 50.8 GHz with the intermediate frequency 800 MHz. Graph showing output of.

26 is a graph showing the conversion loss according to the local oscillation output when the local oscillation frequency is 50 GHz, the IF frequency is 800 MHz, and the output is 7 dBm and the RF frequency is 50.8 GHz.

27 is a plan view of a high pass filter for an NRD guide for blocking a low range and passing a high range in a mixed signal (f _LO ± f _IF ) generated after an up-converter.

<28> FIG. 28: A graph showing the transmission loss according to the frequency of the NRD guide high pass filter of FIG. 27 measured with a network analyzer.

29 is a plan view of a bend type high pass filter having the purpose of reducing the area occupied by the high pass filter for NRD guides and miniaturization thereof.

30 is a graph showing transmission loss according to frequency of the NRD guide bend type high pass filter of FIG. 29 with a network analyzer.

31 is a perspective view of a frequency converter having a form in which a local oscillation unit is mounted inside the frequency converter.

32 is a plan view of a frequency converter having a form in which a local oscillation unit is mounted inside the frequency converter.

33 is a perspective view of a gun diode mount equipped with a gun diode used to cause local oscillation.

34 is a perspective view of a strip resonator for feeding locally oscillated radio waves with an NRD guide.

<35> Fig. 35 is a graph showing the RF output characteristics as the output changes at an intermediate frequency of 800 MHz when the local oscillation frequency is 50 GHz and the output is 7 dBm for a frequency converter equipped with a local oscillation unit inside the frequency converter.

(Explanation of symbols for the main parts of the drawing)

〈36〉 1: Upper conductor plate.

<37> 2: lower conductor plate.

<38> 3, 18, 23, 28, 30, 32, 34, 38, 42, 46, 51, 56, 58, 60, 64,: NRD guideline.

<39> 4, 6, 8, 10, 14, 29, 31, 33, 61, 63, 62: Mode sprayer comprised by inserting the choke type filter 24 into the NRD guide line 23.

<40> 5, 9: ferrite resonator composed of ferrites 25 and 27 and teflon tubes 26

<41> 7: anti-reflective terminal formed by inserting the resistive film 59 into the NRD guide line 58

42, 11: front teflon of an up-converter with voids.

<43> 12, 36: A Schottky diode mount to which a Schottky diode 40 is mounted.

44, 13: rear teflon of the up-converter.

<45> 14, 17, 43, 45, 52, 55: Taper part inserted in the middle of the transmission line to implement a high pass filter (low pass filter).

<46> 16, 44: Bend type cut-off part for cutting low frequency and passing high frequency.

<47> 19, 20, 41, 47, 50, 57: rod antenna

<48> 21: Strip resonator for transmitting local oscillations from the gun diode mount inside the frequency converter to the NRD guide line.

<49> 22: Gun diode mount consisting of gun diode 49 and bias choke 48 for local oscillation inside frequency converter

<50> 24: metal (copper) thin film having a λ / 4 type choke structure

<51> 25, 27: Ferrite disk (ferromagnetic disk)

<52> 39: High-Permittivity Sheet for Impedance Matching of NRD Guides and Schottky Diode Mounts

〈53〉 40: Schottky Diode

<54> 48: Bias choke for applying a bias to the positive (anode) terminal of the gun diode.

<55> 49: gun diode which is an oscillation element.

<56> 54: Straight cut-off unit for cutting low frequencies and passing high frequencies.

<57> f _LO : Local oscillation frequency.

〈58〉 f _IF : Middle frequency.

<59> f _LO ± f _IF : Mixed frequency.

<60> f _LO -f _IF : Low-frequency mixed frequency.

< _LO > f _LO + f _IF : High-frequency mixed frequency.

<62> W1, W2: Dimensions showing a small width and a large width depending on the impedance when the metal thin film to be inserted into the mode compressor is in the form of a choke.

〈63〉 L: Choke (Inductance)

〈64〉 C: Condense (conductance)

〈65〉 L1, L2: Length of taper part among high pass filter (low pass cut off filter)

〈66〉 L3: Length of cutoff part among high pass filter (low pass cut filter)

<76> For the detailed description of the configuration and operation of the present invention, it is divided into a circulator, an isolator, an up-converter, a linear high pass filter, a bend type high pass filter, and a local oscillation part using an internal gun diode. Only the drawings of the frequency converter using the pass filter are presented and the description of the linear high pass filter is additionally made to replace the description of the entire embodiment. It can also be implemented over the millimeter wave band of 50 GHz, allowing modification or implementation in the entire millimeter wave band. The upper and lower conductor plates in the 50 GHz band are 2.7 mm apart. That is, the height of the NRD guide line is 2.7 mm and the width is 3.0 mm.

(Example 1)

1 and 2 are a perspective view and a plan view of a form of inputting local oscillation from the outside of the frequency converter of the present invention. Externally applied local oscillation wave is transmitted to the circulator through the isolator, and there is no gap between one terminal of the circulator and the up-converter, and the circulator is mixed by mixing the signal of intermediate frequency input through the up-converter. The mixed signal is transmitted to the output terminal of the bend type high pass filter, and the high frequency mixed signal passes through and radiates through the antenna 19, and the low frequency mixed signal is reflected and transmitted to the isolator, thereby terminating in the terminator (7). It is absorbed and does not affect the local oscillation part.

<78> FIG. 3 is a block diagram to help explain the frequency converter of the present invention. The local oscillation frequency (f _LO ) generated through the 50 GHz local oscillator is transmitted to the circulator through the isolator, and the mixed signal (f _LO ± f _IF ) through the up-converter is transmitted to the high pass filter through the circulator. . In the highpass filter, only the high pass mixed signal (f _LO + f _IF ) passes through to radiate the RF signal through the antenna, and the blocked low pass mixed signal (f _LO -f _IF ) passes through the circulator to the isolator. It is extinguished at the radioactive end (7).

<79> FIG. 4 is a perspective view of the circulator. Since the circulator is an irreversible device in which NRD guide lines are arranged at intervals of 120 degrees, an unnecessary mode may occur. Thus, by placing the ferrite disks 25 and 26 having a diameter of 3.3 mm and a thickness of 0.32 mm up and down and inserting a Teflon tube 27 in the middle, a bias of 1200 Oe is applied to the ferrite resonators 5 and 9 configured as shown in FIG. The magnetic field is applied and the λ / 4 choke type metal thin film 24 is inserted into the NRD guide line 23 as shown in FIG. 7 between the ferrite resonators 5 and 9 and the NRD guide lines arranged at 120 degree intervals, respectively. Unnecessary modes can be suppressed by inserting the mode compressors 29, 31 and 33.

<80> FIG. 5 shows a configuration and role of the isolator in the frequency converter of the present invention as a schematic diagram showing the flow of radio waves. The basic principle of the isolator is the same as the circulator, but it can be understood that an anti-reflective terminal is mounted at one terminal to serve as a breaker. The local oscillation wave f _LO is input to the NRD guide line 60 and rotated clockwise to be transmitted to the circulator. Then, the mixed low frequency signal (f _LO -f _IF ) cut off from the high pass filter is input through the circulator to the NRD guide line 64, rotates in the clockwise direction, enters the anti-reflective end 7, and disappears. Rarely delivered to the oscillator.

<81> Figures 9 and 10 show the results measured by the network analyzer to confirm the insertion loss and blocking properties of the circulator and isolator described above. Forward insertion loss is less than 1dB and has good characteristics in 50GHz band. In addition, the backward insertion loss, that is, the blocking property, may cause an insertion loss of less than -20 dB over a band of 2 GHz or more, so that radio waves are not transmitted in the reverse direction.

<82> The LSE mode can be suppressed by the metal thin film 24 arranged vertically, and can suppress TE mode by having the filter structure of (lambda) / 4 choke shape. At this time, the length of lambda / 4 is about 1.05mm, w1 is 0.6mm, w2 is 2.4mm to have a proper impedance. The transmission loss characteristics of the LSM mode and the LSE mode by the mode sprayer are shown in FIG. 11. As a result, there is almost no transmission loss in the LSM mode, and the transmission loss of the LSE mode has a value of -20 dB or less over the entire band.

FIG. 8 is a perspective view of the internal projection of the non-reflective end 7 of the isolator shown in FIG. 5. A horizontally grooved resistive film is inserted in the center of the NRD guide line 58. 12 is a graph of VSWR (voltage standing wave ratio) by mounting the anti-reflective terminal 7 to the reflective terminal of the line and measuring the reflection characteristics. As a result, the standing wave ratio has a value of 1.1 or less over the entire band. That is, it can be seen that almost no reflection occurs and is absorbed and disappears.

FIG. 13 is a perspective view of an up-converter without voids. 14 and 15 are plan views and cross-sectional views including a signal f _LO ± f _IF mixed with a signal f _LO of a local oscillation wave incident from a circulator and an IF signal reflected from the circulator. The local oscillation wave (f _LO ) is mixed with the IF signal input to the Schottky diode mount, where (f _LO ± f _IF ) is reflected and returned to the output terminal through the circulator. At this time, the high dielectric constant sheet 39 was inserted between the NRD guide line 38 and the Schottky diode mount 36 to match impedance matching.

Fig. 16 is a Schottky diode mount 36 having a structure in which HSCH9101 Schottky diode 40 of HP is mounted on a chalk-like metal thin film of dielectric substrate 36 having a thickness of 0.3 mm and a dielectric constant of 2.56. .

FIG. 17 illustrates a circuit for supplying a bias voltage and an IF to the Schottky diode mount 36 of FIG. 16. The bias voltage was found to be the lowest when the 3mA current flows through the Schottky diode 40, the VSWR measured according to the frequency at this time is shown in Figure 18. It was found that VSWR does not have a low value but may have a constant VSWR across the entire frequency band.

FIG. 19 places a gap between the NRD guide line 34 and the Schottky diode mount 36 to improve VSWR in the up-converter without the above-described voids. In addition, the method of increasing the coupling of the NRD guide line 34 by placing the front Teflon 35 in the air gap and the high dielectric constant between the front Teflon 35 and the Schottky diode mount 36 for impedance matching. Sheet 39 was inserted.

20 and 21 show a signal f _LO ± f _IF mixed with an IF signal from which a local oscillation wave signal fLO incident from the circulator is reflected with a gap between the Schottky diode mount 36. Is a plan view and a sectional view including the operation of n). The local oscillation wave (f _LO ) is transmitted to the front teflon (35), which is placed with a gap, mixed with the IF signal input to the Schottky diode mount, and (f _LO ± f _IF ) is reflected and returned through the circulator. Passed to the output terminal.

FIG. 22 shows a current of 3 mA flowing through the Schottky diode 40 of the Schottky diode mount 36 by applying a bias voltage as in the case of the up-converter without the above-described gap. This is the result of measuring VSWR. VSWR has the lowest value at 50GHz, but the bandwidth appears narrow.

<90> VSWR according to the IF frequency measured by generating a local oscillation wave having a frequency of 50 GHz from the outside by using the up-converter in which the above-described air gap exists and entering the up-converter through the isolator and the circulator. 23, 24, 25, and 26 show the conversion loss according to the frequency of and IF, the change in output of the mixed signal reflected by the output of IF, and the conversion loss due to local oscillation output.

Fig. 23 is a graph of VSWR measured by a network analyzer with a local oscillation wave output of 50 GHz as 7 dBm, a bias current flowing through the Schottky diode 40 as 3 mA, and a frequency of IF changed to 1 GHz. It has a VSWR value of 2 from 700MHz to 900MHz.

<92> FIG. 24 shows measurements of a local oscillation wave of 50 GHz at 0 dBm and 7 dBm, a bias current flowing through the Schottky diode 40 at 3 mA, an output of IF at 7 dBm, and a frequency of 1 GHz. Conversion loss is shown. The lower the output of the local oscillation wave, the lower the conversion loss value.

<93> FIG. 25 shows the output of the 50 GHz local oscillation wave at 0 dBm and 7 dBm, the bias current flowing through the Schottky diode 40 at 3 mA, and the IFWR 800MHz with the lowest VSWR in the result of FIG. It is a value measured by the output of RF according to the output of the IF when the RF, that is, the mixed signal (f _LO + f _IF ) of the high band of the mixed signal (f _LO ± f _IF ) becomes 50.8 GHz.

Fig. 26 generates a 50 GHz local oscillation wave, sets a bias current flowing to the Schottky diode 40 at 3 mA, fixes the IF frequency at 800 MHz with the lowest VSWR in the result of Fig. 23, and outputs 7 dBm. This is a graph measuring the conversion loss according to the output of local oscillation wave.

<95> As shown in the results of FIGS. 24, 25, and 26, when the output of the local oscillation wave is low, the conversion loss can be reduced, but the output of the RF is lowered. On the contrary, when the output of the local oscillation wave is high, the variation loss is large, but the output of the RF can be increased. It can be considered that there is a trade-off relationship between the two.

<96> Fig. 27 is a plan view of a linear high pass filter or a low stop filter for an NRD guide. The mixed signal transmitted through the circulator outputs the frequency signal of the sum and difference of the local oscillation wave and the IF signal. Since these use the frequency signal of the sum, the frequency signal of the car must be cut off. In other words, a filter that blocks low-frequency mixed signals should be used.

As the high pass filter in the millimeter wave band, a cut-off filter using a waveguide blocking effect is known. In the NRD guide as well, by narrowing the width of the NRD guide line, it is possible to construct a high pass filter capable of blocking the mixed signal of the low pass. The tapers 52, 55 of FIG. 27 help to mix the mixed signal to the cutout 54. At this time, the length of the taper 52, 55 was 30mm by an experimental method. And the length of the interruption | blocking part 54 was also 40 mm by the experimental method. However, the width of the blocking part was 1.77 mm according to the result of setting the blocking frequency to 50 GHz using the characteristic equation of the NRD guide.

<98> FIG. 28 is a graph illustrating the transmission characteristics of the linear high-pass filter designed in FIG. 27, that is, the transmission loss according to the change in frequency from 47 GHz to 53 GHz. As a result, we could get -40dB of transmission loss at 500MHz lower than cutoff frequency. It has been found experimentally that the length of the taper 52, 55 tends to reduce the ripple in the passage area.

<99> FIG. 29 shows a plan view of a bend type high pass filter that can be downsized to be suitable for forming a millimeter wave band system because FIG. 27 is structurally large. The bend of the bend type high pass filter has a bend of 90 degrees and a radius of curvature of 25.8mm, so that the cutoff length is 40.5mm. 30 is a network analyzer for the transmission loss of the bend type high pass filter. As a result, miniaturization is possible while maintaining the characteristics of the linear high pass filter.

(Example 2)

<100> In Example 1, the local oscillation wave was input from the outside by the antenna 20, and was comprised. Embodiment 2 of the present invention relates to a frequency converter that generates a local oscillation wave using a gun diode inside the frequency converter.

31 and 32 are a perspective view and a plan view of a frequency converter for supplying a local oscillation wave by a gun diode.

Fig. 33 is a perspective view of the gun diode mount for causing local oscillation. The oscillation can be caused by mounting the gun diode 49 on the gun diode mount 22 and applying a bias voltage to the anode terminal of the gun diode 49 through the bias choke 48.

<103> FIG. 34 shows the diode resonator 21 with the strip resonator 21 and the mode extractor 4 to transfer the local oscillation wave generated in the gun diode mount of FIG. 33 to the NRD guide through the mode compressor 4. It is configured by mounting between).

35 shows the frequency of the local oscillation wave generated from the gun diode mount at 50 GHz, the output at 7 dBm, the bias current flowing through the Schottky diode at 3 mA, and the IF frequency at 800 MHz. The graph shown.

<105> With the diversified use of frequency, attention has been paid to various fields such as LAN for millimeter wave band, short range wireless communication for traffic control, and various sensors. The configuration of each of these systems requires the realization of a compact and high performance millimeter wave integrated circuit.

<106> NRD guides have been researched and developed, and in terms of transmission loss, dielectric lines have an advantage over millimeter wave bands over metal lines. However, there is little radiation in the curve and discontinuities compared to the image or reverse strip lines.

<107> The present invention has proved the possibility of configuring an integrated circuit in the millimeter wave band. In addition, the use of up-converters in the frequency converter allows compatibility with existing RF or optical systems. In addition, miniaturization is possible by using a bend type high pass filter.

Claims (5)

Applying a local oscillation wave from the outside to deliver to the circulator through the isolator; Mixing the local oscillation wave with an intermediate frequency signal input through the up-converter without air gap and transferring the mixed signal to the output terminal of the circulator; In the linear high pass filter, the high pass mixed signal passes through and radiates through the antenna; A low frequency mixed signal is reflected and transmitted to the isolator, absorbed by the terminator, and configured so as not to affect the local oscillator. The method of claim 1, And improve the VSWR over a particular band by configuring a gap between the up-converter and the circulator in the frequency converter. Generate a local oscillation wave from the gun diode mount with the gun diode mounted therein; Applying a local oscillation wave to the NRD guide using the strip resonator and transferring it to the circulator through the isolator; Mixing the local oscillation wave with an intermediate frequency signal input through the up-converter without air gap and transferring the mixed signal to the output terminal of the circulator; In the linear high pass filter, the high pass mixed signal passes through and radiates through the antenna; A low-frequency mixed signal is reflected and transmitted to the isolator, absorbed by the terminator and configured so as not to affect the local oscillator. The method of claim 3, wherein And improve the VSWR over a particular band by configuring a gap between the up-converter and the circulator. The method according to claim 1 and 3, And a bend type high pass filter is inserted in order to reduce the structure of the linear high pass filter of the frequency converter.