Dielectric radio frequency (RF) bidirectional coupler with power divider / combiner function

Abstract

An ultra-wideband radio frequency bidirectional coupler is provided. An ultra-wideband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) having power divider / combiner functionality for signals having frequencies reaching up to 300 GHz comprises a free propagation region substrate (210) having a pair of opposing edges (240A, 240B), a first group of access ports (P-L1 to P-LM) established along at least one edge of said free propagation region substrate (210) and a second group of access ports (P-R1 to P-RM) established along an opposite edge of said free propagation region substrate (210), wherein the first and second groups of access ports (P-L1 to P-LM), (P-R1 to P-RN) are tuned to a low cutoff frequency f in the microwave or millimeter wave range. CL The interconnects are provided with dielectric waveguide structures (DW-L1 to DW-LM), (DW-R1 to DW-RN) that provide high-pass characteristic interconnects operating over a high frequency range starting from .

Description

[Technical Field]

[0001] This invention generally relates to a radio frequency bidirectional coupler having power divider / combiner functions. A radio frequency bidirectional coupler is a type of device used in the field of radio frequency engineering that enables the energy of a radio frequency signal propagating through one of M inputs to be divided among N groups of outputs (divider), and the energy propagating through various inputs to be combined into a common output (combiner). This invention discloses a directional coupler structure based on a dielectric waveguide that is wideband and broadband. Wideband means that it operates over a wide frequency range, and broadband means that it is suitable for modulated signals that occupy a wide bandwidth. [Background technology]

[0002] Radio frequency (RF) systems operate by handling signals in the form of guided electromagnetic waves with frequencies ranging from approximately 30 MHz in the spectrum to the millimeter (30 GHz to 300 GHz) and terahertz (300 GHz to 3000 GHz) regions. When handling these signals, RF systems may need to divide the radio frequency signal propagating through waveguides into several copies, varying the amount of energy (division ratio) within each copy, and delivering each through different output waveguides. This function constitutes a power divider. The inverse function, which combines different RF signals into a common output, is also relevant, constituting a power combiner.

[0003] A specific case of such functionality is a passive device known as a bidirectional coupler, schematically shown in Figure 1. This figure shows a bidirectional coupler (100) with four access ports. An input signal arrives at the directional coupler at its input port (P1), from which a predetermined amount of energy is coupled to the output transmission port (P2) and the remaining amount to a second output known as the coupling port (P4). The input signal power at input port (P1) is typically split between output ports using closely spaced transmission lines, with the energy passing through one waveguide coupled to the other by evanescent wave leakage. In some devices, the reflection of the signal that exits through output port (P2) and returns to the device enters this port (P2) and is routed to an isolation port (P3). Since any port can be an input, the device is bidirectional, and as a result, directly connected ports become transmission ports, adjacent ports become isolation ports, and diagonally opposite ports become coupling ports.

[0004] Directional couplers and power dividers have many applications. These include providing signal samples for measurement or monitoring, feedback, combining feeds with antennas, antenna beamforming, providing taps for cable distribution systems such as cable TV, and separating transmitted and received signals in telephone lines.

[0005] Most current directional couplers are limited to the microwave frequency range (3 GHz to 30 GHz) using transmission line designs. Therefore, there is a need for an ultra-wideband directional coupler that covers a wide frequency range including the range of coaxial standards (e.g., 1 mm connector, up to 110 GHz) and can operate independently of the various rectangular waveguide standards used by radio frequency engineering techniques for the above frequencies (e.g., WR8 - 90 GHz to 140 GHz, WR6 - 110 GHz to 170 GHz, and WR5 - 140 GHz to 220 GHz). The present invention satisfies this requirement and enables an extremely wide operating frequency range. [Overview of the Initiative]

[0006] The present invention proposes a novel bidirectional coupler having power divider / combiner functions based on a dielectric waveguide structure, which extends the operating frequency range of the device to cover the microwave (3GHz to 30GHz), millimeter (30GHz to 300GHz), and terahertz (300GHz to 3000GHz) wave ranges.

[0007] The coupler comprises a free-propagation region substrate having a pair of opposing edges. Furthermore, the coupler comprises a first group of access ports along a first of the opposing edges of the free-propagation region substrate, and a second group of access ports along a second of the opposing edges of the free-propagation region substrate. The first and second groups of access ports have a low cutoff frequency f in the microwave or millimeter-wave range. CL It features a dielectric waveguide structure that provides a high-pass filter transfer function that operates over a high-frequency range starting from .

[0008] In the first example, the first of the opposing edges may be formed as an arc of a circle having radius r1, with its center OA located closer to the second edge.

[0009] In other examples, the second edge of the opposing edges may be formed as the arc of a second circle having radius r2, with its center OB located closer to the first edge.

[0010] In other examples, the arcs of a circle can have the same radius (r1=r2), and the centers OA and OB are on one of the port axes.

[0011] In some examples, the ultra-wideband radio frequency bidirectional further includes multiple arms, which assign a first group of access ports and a second group of access ports.

[0012] In some examples, dielectric waveguide structures are established on a free-propagation region substrate.

[0013] In some examples, the dielectric waveguide structure is embedded in a free-propagation region substrate.

[0014] In a preferred example, the dielectric waveguide "DW" structure has tapered ends with a DW tapering profile. The first and second groups of access ports have high cutoff frequencies f in the millimeter / submillimeter wave range. CH It also features a tapered slot antenna "TSA" that provides a bandpass filter transfer function that operates over a low frequency range up to [a certain frequency].

[0015] The tapered slot antenna has a TSA taper shape around the first tapered end of the dielectric waveguide structure, and the TSA taper shape matches the DW taper shape.

[0016] In some examples, the TSA taper shape and DW taper shape are linearly tapered.

[0017] In some examples, the TSA taper shape and DW taper shape are exponentially tapered.

[0018] In some examples, the TSA taper shape and DW taper shape are Fermi tapered.

[0019] Another preferred example is an ultra-wideband bidirectional coupler with power divider / combiner functionality, with a low cutoff frequency f in the DC (or very low frequency, down to a few kHz) to millimeter wave range. CL The structure includes a second substrate on which a low-frequency directional coupler configured to operate up to f is established. In this structure, multiple transmission line and waveguide transitions operate from low frequencies to f CH To achieve a directional coupler with an operating frequency range up to [specify frequency range], a low-frequency directional coupler and a tapered slot antenna are connected.

[0020] In another preferred example, the ultra-wideband bidirectional coupler having a power splitter / combiner function includes two first access ports along at least one edge of the free propagation region substrate having two dielectric waveguide structures with tapered ends, and two second access ports along the opposite edge of the free propagation region substrate having two dielectric waveguide structures with tapered ends. In this example, the four dielectric waveguide structures have a DW taper shape, and the ultra-wideband bidirectional coupler further includes four tapered slot antennas that operate over a low frequency range up to a high cutoff frequency f CH in the millimeter wave range, providing low-pass characteristics, and the tapered slot antennas have a TSA taper shape around the first tapered end of the dielectric waveguide structure, and the TSA taper shape matches the DW taper shape.

[0021] In other examples, the dielectric waveguide structure can include at least one tapered end.

[0022] In other examples, the free propagation region substrate can have a different dielectric constant from the dielectric waveguide structure.

[0023] In other examples, the free propagation region substrate can include an absorber.

[0024] In other examples, the free propagation region substrate can include a dielectric material.

Brief Description of the Drawings

[0025] For a better understanding of the above description and for the sole purpose of providing examples, several non-limiting drawings schematically showing practical embodiments are included. [Figure 1] Showing a directional coupler as commonly understood by experts in the field of radio frequency engineering. [Figure 2A] Showing the ultra-wideband bidirectional coupler according to the present invention. [Figure 2B] Showing the ultra-wideband bidirectional coupler of Figure 2A further including a tapered slot antenna for emitting a radio frequency signal to a dielectric waveguide according to the present invention. [Figure 3] A specific example of the ultra-wideband bidirectional coupler according to the present invention, having four access ports, is shown. [Figure 4A] Figure 3 shows a 3D view of a specific example of an ultra-broadband bidirectional coupler, where the dielectric waveguide access structure is located on a free-propagation region substrate. [Figure 4B] A 3D diagram of an example of an ultra-broadband bidirectional coupler according to the present invention, in which a dielectric waveguide access structure is embedded in a free-propagation region substrate, is shown. [Figure 4C] A 3D diagram of an example of an ultra-broadband bidirectional coupler according to the present invention, in which a dielectric waveguide access structure is embedded in a free-propagation region substrate, is shown. [Figure 4D] A 3D diagram of an example of an ultra-broadband bidirectional coupler according to the present invention, in which a dielectric waveguide access structure is embedded in a free-propagation region substrate, is shown. [Figure 5A] Figure 3 shows the E-field amplitude distribution at different frequencies in the range of 20 GHz to 300 GHz for a specific example of the ultra-wideband bidirectional coupler according to the present invention. [Figure 5B] Figure 3 shows the E-field amplitude distribution at different frequencies in the range of 20 GHz to 300 GHz for a specific example of the ultra-wideband bidirectional coupler according to the present invention. [Figure 5C] Figure 3 shows the E-field amplitude distribution at different frequencies in the range of 20 GHz to 300 GHz for a specific example of the ultra-wideband bidirectional coupler according to the present invention. [Figure 5D] Figure 3 shows the E-field amplitude distribution at different frequencies in the range of 20 GHz to 300 GHz for a specific example of the ultra-wideband bidirectional coupler according to the present invention. [Figure 5E] Figure 3 shows the E-field amplitude distribution at different frequencies in the range of 20 GHz to 300 GHz for a specific example of the ultra-wideband bidirectional coupler according to the present invention. [Figure 5F] Figure 3 shows the E-field amplitude distribution at different frequencies in the range of 20 GHz to 300 GHz for a specific example of the ultra-wideband bidirectional coupler according to the present invention. [Figure 5G]Figure 3 shows the E-field amplitude distribution at different frequencies in the range of 20 GHz to 300 GHz for a specific example of the ultra-wideband bidirectional coupler according to the present invention. [Figure 5H] Figure 3 shows the E-field amplitude distribution at different frequencies in the range of 20 GHz to 300 GHz for a specific example of the ultra-wideband bidirectional coupler according to the present invention. [Figure 6] The simulated S-parameter amplitudes of a specific example of the ultra-wideband bidirectional coupler shown in Figure 3 according to the present invention are shown. [Figure 7] Another example of the ultra-wideband bidirectional coupler according to the present invention, which has an extended operating frequency range toward lower frequencies, is shown. [Modes for carrying out the invention]

[0026] Figure 2A shows a proposed dielectric structure for a bidirectional coupler (200A) having power divider / combiner functionality according to the present invention. The proposed structure (200A) comprises a first group of M input access ports on the left side of the figure (P-L1) to (P-LM), and the M input access ports are coupled to a second group of N output access ports on the right side of the figure (P-R1) to (P-RN) via a free-propagation region substrate (210). The left edge (240A) of the free-propagation region along which the access ports (P-L1) to (P-LM) are provided is formed by an arc of a circle with radius r1, where the center OA is closer to the opposite edge (240B) of the free-propagation region substrate (210). The edge (240B) of the free-space propagation region, along which the output access ports (P-R1) to (P-RN) are located, is formed by the arc of a circle with radius r2, where the center OB is closer to the opposite edge (240A) of the free-space propagation region.

[0027] In a preferred implementation, the arcs of the input and output waveguide circles can have the same radius (r1=r2=r), and the centers OA and OB are located on one of the port axes.

[0028] The access ports (PL1~PLM) and (PR1~PRM) are equipped with dielectric waveguide structures (DW-L1)~(DW-LM) on the left side of the figure and (DW-R1)~(DW-RN) on the right side of the figure, and in this particular example, all dielectric waveguide structures have tapered ends. Advantageously, the dielectric waveguide structures couple the electromagnetic energy propagating through them to the free-propagation region substrate (210), reducing inter-port insertion losses that are now proportional to the distance between the input and output ports rather than the square spacing of the DW structure, by the distance d between the input and output ports, which is not constrained by the far-field reference. d>>2D 2 / λ Here, D is the maximum waveguide structure dimension and λ is the signal wavelength. However, the DW structure radiates within a specific region that shifts along its axis to vary the signal frequency. At high frequencies, the phase center is close to the tip of the DW, so the distance between the two radiation bands both conforms to the far-field standard.

[0029] The isolation between access ports (PL1-PLM) and (PR1-PRM) is advantageously reduced by confining electromagnetic energy within dielectric waveguides, enabling a compact configuration without causing crosstalk between adjacent access ports.

[0030] Figure 2B shows a preferred implementation for another structure (200B). The structure (200B) comprises a plurality of arms that allocate a first group of access ports (PL1~PLM) and a second group of access ports (PR1~PRM). The structure (200B) includes an emission structure for radio frequency signals within the dielectric waveguide DW. Advantageously, the emission structure excites only the fundamental mode of the dielectric waveguide DW for each frequency within the operating frequency range. The emission structure comprises a tapered end of the dielectric waveguide structure and a tapered slot antenna, both having the same tapered shape. In the figure, it is shown that for all access ports, the emission structure has tapered slot antennas on the left side (TSA-L1~TSA-LM) and on the right side (TSA-R1~TSA-RN) around the tapered ends of the dielectric waveguide structures (DWL1~DWLM), (DWR1~DWRN) having a matching linear tapered shape between the tapered slot antenna and the dielectric waveguide structure.

[0031] The dielectric waveguide structures (DWL1~DWLM), (DWR1~DWRN) have high-pass filter characteristics and enable electrical interconnection of radio frequency signals having frequencies above the low cut-off frequency (f CL ). The dielectric waveguide structures (DWL1~DWLM), (DWR1~DWRN) cover a wide frequency range including the terahertz wave range (i.e., 300~3000 GHz) and beyond, and in the microwave range (i.e., 3 GHz~30 GHz) or in the millimeter wave range (i.e., 30 GHz~300 GHz), for example, at an operating frequency of 60 GHz, can be designed to have a low cut-off frequency (f CL ). Preferably, the ultra-wideband directional coupler has an adjustable low cut-off frequency (f CL ) of 65 GHz by changing the structural dimensions.

[0032] The tapered slot antennas (TSA-L1~TSA-LM), (TSA-R1~TSA-RN) have low-pass filter characteristics and have a high cut-off frequency (f CHThis enables the electrical interconnection of signals up to ). Tapered slot antennas can be designed as transmission lines with contact tips at their ends to establish electrical contact with the access ports of the device, and can be designed to operate in a range starting from 0 Hz and extending to the millimeter wave range (i.e., 30 GHz to 300 GHz, for example, 100 GHz operating frequency).

[0033] As shown in the figure, the tapered slot antennas (TSA-L1 to TSA-LM) and (TSA-R1 to TSA-RN) have a tapered shape around the first tapered end of the dielectric waveguide structure (DWL1 to DWLM) and (DWR1 to DWRN). Preferably, the TSA tapered shape and the DW tapered are linearly tapered. In other examples, different tapered shapes may be implemented, for example, as Fermi tapering or exponential tapering.

[0034] In a preferred embodiment for broadband operation, the tapered slot antenna starts at a low frequency and has a dielectric waveguide structure with a low cutoff frequency above (f CH >f CL、 For example, it operates over a frequency range exceeding 60 GHz (as in the previous example). Preferably, the ultra-wideband bidirectional coupler has a higher cutoff frequency (f) of at least 300 GHz. CH ) has. The cutoff frequency can be increased, for example, by reducing the thickness of the components of the ultra-wideband bidirectional coupler and / or by using materials with different dielectric constants.

[0035] Figure 3 shows a novel bidirectional coupler (300) with power divider / combiner functionality according to the present invention, as well as other bidirectional couplers. The ultra-wideband bidirectional coupler (300) has four access ports, namely two input ports (P-L1 and P-L3) and two output ports (P-R4 and P-R2). A signal enters the directional coupler through the input port (P-L1), coupling a specified amount of electromagnetic power to the output transmission port (P-R2) and the other amount to a second output known as the coupling port (P-R4). There is a second input port (P-L3) known as the isolation port.

[0036] The access ports of the ultra-wideband bidirectional coupler (300) include dielectric waveguide structures with tapered ends, namely, a dielectric waveguide structure (DW-L1) at the input port (P-L1), a dielectric waveguide structure (DW-R2) at the transmission port (P-R2), a dielectric waveguide structure (DW-R4) at the coupling port (P-R4), and a dielectric waveguide structure (DW-L3) at the isolation port (P-R1). The dielectric waveguide structures have a low cutoff frequency (f) within the microwave or millimeter wave range. CL It provides a high-pass filter transfer function that operates over a high-frequency range starting from ).

[0037] Optionally, the access ports (P-L1), (P-R2), (P-L3), and (P-R4) may include a transmitting structure that injects a signal into the corresponding dielectric waveguide. The transmitting structure comprises a tapered slot antenna and a tapered end of the dielectric waveguide, with the taper of both structures having the same tapered shape. The tapered slot antennas (TSA-L1), (TSA-R2), (TSA-L3), and (TSA-R4) have high cutoff frequencies (f) ranging from the low frequency range to the millimeter wave range. CH It provides low-pass characteristics that operate up to ). The tapered slot antenna has a matching pattern that defines a tapered coupler, preferably a linear taper shape around the tapered end of the dielectric waveguide at the access port, thereby achieving ultra-broadband excitation of the directional coupler in the single-mode region, together with the corresponding tapered end of the dielectric waveguide.

[0038] A characteristic of this structure is that the amount of power coupled from one input port to the output port can be controlled by the relative angle between their respective positions at opposite edges of the free propagation region. In Figure 3 of the ultra-wideband bidirectional coupler (300), the electromagnetic energy of the input port (P-L1) is divided between the output ports (P-R2) and (P-R4).

[0039] Maximum power coupling occurs when the dielectric waveguides of the input port (P-L1) and the transmission port (P-R2) are positioned along the same axis, as in the ultra-wideband bidirectional coupler (300) shown in Figure 3. In this situation, the transmitted signal level between ports (P-L1) and (P-R2) is controlled by the taper angle e of the (DW-L1) antenna and the distance d between the tips of the (DW-L1, DW-R2) antennas. The smaller both e and d are, the greater the transmitted signal level.

[0040] In the example in Figure 3, to achieve an ultra-wideband operating frequency range, structures (DW-R2) and (DW-R4) may point toward the phase center of structure (DW-L1). Similarly, DW structures (DW-L1) and (DW-L3) may also point toward the phase center of DW structure (DW-R2). Since the phase center of this structure changes with frequency along the antenna axis, a trade-off is established, allowing for the selection of the frequency to which the phase plane points, thereby setting an upper frequency limit for the bandwidth of the structure.

[0041] As shown in Figure 3, in this example, DW structure (DW-L1) points toward DW structure (DW-R2). DW structure (DW-R4) points toward the phase center of structure (DW-L1) at 260 GHz. Length c determines the distance between the phase center and the tip of DW structure (DW-L1). In this particular example, DW structure (DW-L3) points toward the phase center of DW structure (DW-R2) at 260 GHz.

[0042] When the input and output ports are not on the same axis, as in the ultra-wideband bidirectional coupler (300) shown in Figure 3, the coupling level between the input and output ports is controlled by the relative angle between their positions. In this example, angle a controls the coupling ratio between the input port (P-L1) and the transmission port (P-R4). Similarly, angle b controls the coupling ratio between the output port (P-R2) and the isolation port (P-L3). Although both angles are equal in the figure, a and b may be designed independently to achieve different coupling ratios between ports (P-L3) and (P-R2) relative to (P-L1) and (P-R4). The coupling ratio decreases as the angle increases.

[0043] In this particular embodiment, as shown in the enlarged view of Figure 3, the tapered slot antenna (TSA-L3) tapered shape (300a) and DW tapering are linearly tapered. However, other tapered shapes can be implemented, for example, such as the tapered slot antenna (TSA-L3) tapered shape (300b) and DW tapered shape being exponentially tapered, or the (TSA-L3) tapered shape (300c) and DW tapered shape being Fermi tapered.

[0044] Other examples with different trade-offs are possible, which allow for either raising the specifications of the device in the target subband or increasing the bandwidth. To avoid reflections in the dielectric material, absorbers can be placed at the edge of the free propagation region (310).

[0045] Figure 4A shows a 3D diagram of an ultra-broadband bidirectional coupler (300) when dielectric waveguides and free propagation regions, namely a free propagation region (310), four DW structures (DW-L1, DW-R2, DW-L3, DW-R4), and tapered slot antennas (TSA-L1, TSA-R2, TSA-L3, TSA-R4), are stacked, which can be realized with materials of equal or different dielectric constants.

[0046] In another example, a single-layer alternative embodiment can be obtained by embedding DW structures (DW-L1, DW-R2, DW-L3, DW-R4) in the free-propagation region (310) to obtain a more compact system. This embedding suggests any fabrication method that achieves defining a dielectric waveguide structure by creating a dielectric constant difference within the free-propagation region, i.e., by either etching pores to reduce the dielectric constant around the DW structures, for example, or by assembling components with different dielectric constants. In this regard, Figure 4B shows a 3D view of an ultra-broadband bidirectional coupler (400A) in which DW structures (DW-L1, DW-R2, DW-L3, DW-R4) are embedded in the free-propagation region (310) and the DW structures (DW-L1, DW-R2, DW-L3, DW-R4) are truncated.

[0047] Figure 4C shows a 3D view of an ultra-broadband bidirectional coupler (400B) in which DW structures (DW-L1, DW-R2, DW-L3, DW-R4) are embedded in a free propagation region (310), and which includes a transmit structure tapered slot antenna (TSA-L1, TSA-R2, TSA-L3, TSA-R4) in the access port, with the tapered slot antenna established on the dielectric material of the free propagation region.

[0048] Figure 4D shows a 3D diagram of an ultra-broadband bidirectional coupler (400C) in which the free propagation region (310) is made of the same dielectric material as the DW structure, and the DW structure has truncated edges.

[0049] The operating characteristics of the ultrawideband bidirectional coupler (300) shown in Figures 3 and 4A were characterized by full-wave simulation. The obtained E-field amplitude distributions at different frequencies in the range of 20 GHz to 300 GHz are shown in Figures 5A to 5H. As can be seen from these figures, most of the power of the input signal at the first port (P-L1) is transferred through the structure to the second port (P-R2) in the single-mode region. A small portion of the input power is diverted towards port (P-R4). As shown in the figure, a smaller amount of signal power arrives at port (P-L3). Being in the single-mode region allows for a unique definition of the phase between ports, thereby enabling its use for measurement purposes as shown in Figure 1.

[0050] Figure 6 shows the simulated S-parameter amplitudes (in dB): S11(601) (input port matching), S21(602) (transmission between ports (P-L1) and (P-R2)), S13(603) (coupling between incident port P-L1 and isolated port P-L3), and S14(604) (coupling to coupled port (P-R4)).

[0051] The transmission between ports (P-L1, P-R2), i.e., S21(602), remains flat from 65 GHz to at least 300 GHz. The insertion loss is approximately 4 dB. The coupling between ports (P-L1, P-R4), i.e., S14(604), is not constant with respect to frequency, and the directivity of the coupler increases at higher frequencies. Since the curve is smooth, this effect can be easily compensated by path calibration. The amplitude port matching S11(601) is below -15 dB across the entire bandwidth and below -20 dB at frequencies above 80 GHz. The isolation between ports (P-L1, P-L3), i.e., S13(603), is greater than 25 dB across the entire bandwidth.

[0052] The ultra-wideband coupler (300) functions as a bidirectional coupler. When port (P2) functions as the source of the incident signal, port (P-L1) functions as the transmission port, port (P-L3) functions as the coupling port, while port (P-R4) functions as the isolation port. The parameters for matching, transmission, coupling, and isolation can be the same as in Figure 6, for example, S22=S11(601), S12=S21(602), S32=S41(604), and S42=S31(603).

[0053] If a transmitter is connected to port (P-L1) and two receivers are connected to ports (P-L3, P-R4), then (P-L4) is optional, and port (P-R2) is a bidirectional (input and output) port. In a realistic scenario, port (P-R2) would be connected to an antenna, waveguide, or connector. For communication applications, an antenna may be placed at port (P-R2). For measurement applications, port (P-R2) would be connected to a DUT (device under test). The signal received at port (P-L3) would be proportional to the incident signal to the DUT, and the signal received at port (P-R4) would be proportional to the incident signal to the DUT.

[0054] Figure 7 shows a coupler (700) that functions with DC extension, which is a solution for extending the operating frequency range of the bidirectional coupler (300) structure in the low frequency range toward DC. Coupler (700) includes a bidirectional coupler (300) and further includes a low-frequency directional coupler (750). The low-frequency directional coupler (450) functions at frequencies up to f0 = 65 GHz. The low-frequency directional coupler (450) includes ports (P-L1', P-R2', P-L3', P-R4'). The ports (P-L1', P-R2', P-L3', P-R4') can be used to excite the fundamental mode of DW for all frequencies above f0 and are connected to the ends of the transmission structure (TSA-L1, TSA-R2, TSA-L3, TSA-R4) via metal wire conforming to bifilar wire (720), which is suitable for integration with a low-frequency directional coupler (700).

[0055] At frequencies above f0, the signal is efficiently coupled from the port through the structures (TSA-L1, TSA-R2, TSA-L3, and TSA-R4) to the DW structures (DW-L1, DW-R2, DW-L3, and DW-R4), as shown in Figures 5 and 6. At frequencies below f0, the signal propagates from the port through the structure TSAs along the bifilar wire (720) without being coupled to the DW structures. One of several transitions can be incorporated from the bifilar wire (720) to the low-frequency directional coupler ports (P-L1', P-R2', P-L3', and P-R4'). For illustrative purposes, Figure 7 shows a CPW port and a low-frequency directional coupler (700) with a transition between the bifilar wire (720) and the CPS and CPW waveguides.

[0056] The transition and low-frequency directional coupler (750) are positioned on a substrate (710) that can be placed above (or below) the dielectric coupler (300) at a sufficient distance. Since the wave propagates in a 2D plane (within the free propagation region (210)), there is no radiation in the normal direction, and a compact configuration can be achieved. The distance between the two couplers (300, 750) must be large enough to avoid near-field coupling between them. Furthermore, the present invention includes the following aspects. [Aspect 1] A broadband and broadband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) having power divider / combiner functionality for signals with frequencies reaching up to 300 GHz, A free propagation region substrate (210) having a pair of opposing edges (240A, 240B), A first group of access ports (P-L1~P-LM) established along the first edge (240A) of the pair of opposing edges (240A, 240B), A second group of access ports (P-R1~P-RM) established along the second edge (240B) of the pair of opposing edges (240A, 240B), Equipped with, The first and second groups of the aforementioned access ports (P-L1~P-LM) and (P-R1~P-RN) are: It features dielectric waveguide structures (DW-L1~DW-LM), (DW-R1~DW-RN) that provide high-pass filter transfer functions operating over a high-frequency range starting from a low cutoff frequency fCL in the microwave or millimeter-wave range. Broadband and wideband radio frequency bidirectional couplers. [Aspect 2] In the ultra-wideband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) described in Embodiment 1, An ultra-wideband radio frequency bidirectional coupler in which the first edge (240A) of the pair of opposing edges is formed as an arc of a circle having radius r1, with its center OA located closer to the second edge (240B). [Aspect 3] In the ultra-wideband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) described in Embodiment 2, An ultra-wideband radio frequency bidirectional coupler in which the second edge (240B) of the pair of opposing edges is formed as the arc of a second circle having radius r2, with its center OB located closer to the first edge (240A). [Aspect 4] An ultra-wideband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) according to embodiment 3, where r1 = r2. [Aspect 5] In an ultra-wideband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) described in any one of embodiments 1 to 4, Equipped with multiple arms, The plurality of arms are assigned a first group of access ports (P-L1 to P-LM) and a second group of access ports (P-R1 to P-RN). Ultra-wideband radio frequency bidirectional coupler. [Aspect 6] The dielectric waveguide structures (DW-L1 to DW-LM), (DW-R1 to DW-RN) are established on the free propagation region substrate (310) in an ultra-wideband radio frequency bidirectional coupler (300) according to any one of embodiments 1 to 5. [Aspect 7] The dielectric waveguide structures (DW-L1 to DW-LM) and (DW-R1 to DW-RN) are embedded in the free propagation region substrate (310), in an ultra-wideband radio frequency bidirectional coupler (400A, 400B) according to any one of embodiments 1 to 5. [Aspect 8] In an ultra-wideband radio frequency bidirectional coupler (200B, 300) described in any one of embodiments 1 to 7, The dielectric waveguide structures (DW-L1~DW-LM), (DW-R1~DW-RN) are provided with tapered ends having a defined tapered shape, The first and second groups of the access ports (P-L1~P-LM) and (P-R1~P-RN) further comprise tapered slot antennas (TSA-L1~TSA-LM) and (TSA-R1~TSA-RN) that provide a bandpass filter transfer function operating over a low frequency range up to a high cutoff frequency fCH in the millimeter wave range. The aforementioned tapered slot antennas (TSA-L1~TSA-LM), (TSA-R1~TSA-RN) are equipped with a TSA tapered shape (300a, 300b, 300c), The first tapered ends of the dielectric waveguide structures (DW-L1~DW-LM) and (DW-R1~DW-RN) are located between the tapered slot antennas (TSA-L1~TSA-LM) and (TSA-R1~TSA-RN). The aforementioned TSA taper shape (300a, 300b, 300c) matches the aforementioned DW taper shape. Ultra-wideband radio frequency bidirectional coupler. [Aspect 9] The ultra-wideband radio frequency bidirectional coupler (200B) according to embodiment 8, wherein the TSA taper shape (300a) and the DW taper shape are linearly tapered. [Aspect 10] The ultra-wideband radio frequency bidirectional coupler (200B) according to embodiment 8, wherein the TSA taper shape (300b) and the DW taper shape are exponentially tapered. [Aspect 11] The ultra-wideband radio frequency bidirectional coupler (200B) according to embodiment 8, wherein the TSA taper shape (300c) and the DW taper shape are Fermi tapered. [Aspect 12] In the ultra-wideband bidirectional coupler (700) described in any one of embodiments 1 to 11, A low-frequency directional coupler (750) having an operating frequency range that starts from a low frequency in the DC or kilohertz range and reaches a low cutoff frequency fDCH in the millimeter wave range, Here, fDCH > low cutoff frequency fCL of the dielectric waveguide structure, and Multiple transmission lines (720) and waveguide transitions connect the low-frequency directional coupler (750) and the tapered slot antennas (TSA-L1~TSA-LM), (TSA-R1~TSA-RN) to the combined operating frequency range up to fCH, Furthermore, it is equipped with an ultra-wideband bidirectional coupler (700). [Aspect 13] In the ultra-wideband bidirectional coupler (300) described in embodiment 6 or 7, Two first access ports (P-L1 to P-L3) along at least one edge of the free propagation region substrate (310) having a dielectric waveguide structure (DW-L1 to DW-L3) with tapered ends, Two second access ports (P-R4~P-R2) along the opposite edge of the free propagation region substrate (310) having a dielectric waveguide structure (DW-R4~DW-R2) with tapered ends, Equipped with, The tapered end of the dielectric waveguide structure (DW-L1) points toward the tapered end of the dielectric waveguide structure (DW-R2), The tapered end of the dielectric waveguide structure (DW-R4) points toward the tapered end of the dielectric waveguide structure (DW-L1), The tapered end of the dielectric waveguide structure (DW-L3) points towards the tapered end of the dielectric waveguide structure (DW-R2). Ultra-wideband bidirectional coupler (300). [Aspect 14] In the ultra-wideband bidirectional coupler (300) described in Embodiment 13, The dielectric waveguide structures (DW-L1~DW-L3), (DW-R2~DW-R4) have a DW tapered shape. The system further includes tapered slot antennas (TSA-L1~TSA-L3), (TSA-R2~TSA-R4) that provide low-pass characteristic interconnects operating over a low frequency range up to a high cutoff frequency fCH in the millimeter-wave range, The tapered slot antennas (TSA-L1~TSA-L3), (TSA-R2~TSA-R4) are provided with TSA tapered shapes (300a, 300b, 300c) around the first tapered ends of the dielectric waveguide structures (DW-L1~DW-L3), (DW-R2~DW-R4), The aforementioned TSA taper shapes (300a, 300b, 300c) match the aforementioned DW taper shapes. Ultra-wideband bidirectional coupler (300). [Aspect 15] The dielectric waveguide structures (DW-L1 to DW-LM), (DW-R1 to DW-RN) are provided with at least one truncated end, and the ultra-wideband radio frequency bidirectional coupler (400A, 400C) is according to any one of embodiments 1 to 7. [Aspect 16] The free propagation region substrate (310) has a dielectric constant different from that of the dielectric waveguide structure (DW-L1~DW-LM), (DW-R1~DW-RN), and is an ultra-broadband bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) according to any one of embodiments 1 to 15. [Aspect 17] The free propagation region substrate (310) comprises an absorber, an ultra-broadband bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) according to any one embodiment of embodiments 1 to 16. [Aspect 18] The ultra-broadband bidirectional coupler (400C) according to any one of embodiments 1 to 3, wherein the free propagation region substrate (310) comprises a dielectric material. [Aspect 19] In an ultra-wideband bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) described in any one of embodiments 1 to 18, The arc of the circle for the first group of access ports (P-L1 to P-LM) is equal to the radius r2 of the arc of the second circle, The centers (OA, OB) of the two circles are aligned radially. Ultra-wideband bidirectional couplers (200A, 200B, 300, 400A, 400B, 400C).

Claims

1. Broadband and broadband radio frequency bidirectional couplers (200A, 200B, 300, 400A, 400B, 400C) having power divider / combiner functions for signals having frequencies reaching up to 300 GHz, A free propagation region substrate (210) having a pair of opposing edges (240A, 240B), A first group of access ports (P-L1 to P-LM) arranged along the first edge (240A) of the pair of opposing edges (240A, 240B), A second group of access ports (P-R1 to P-RM) arranged along the second edge (240B) of the pair of opposing edges (240A, 240B), Equipped with, The first and second groups of the aforementioned access ports (P-L1 to P-LM) and (P-R1 to P-RN) are: Equipped with dielectric waveguide structures (DW-L1 to DW-LM), (DW-R1 to DW-RN), Since the free propagation region substrate (210) is configured to operate as a two-dimensional free-space propagation region, the dielectric waveguide structures (DW-L1 to DW-LM), (DW-R1 to DW-RN) have a low cutoff frequency f in the microwave or millimeter-wave range. ＣＬ It provides a high-pass filter transfer function that operates over a high-frequency range starting from, Broadband and wideband radio frequency bidirectional couplers.

2. In the ultra-wideband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) described in claim 1, An ultra-wideband radio frequency bidirectional coupler, wherein the first edge (240A) of the pair of opposing edges is formed as an arc, and the arc is the arc of a first circle having radius r1, and the center OA of the first circle is located closer to the second edge (240B) than to the first edge (240A).

3. In the ultra-wideband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) described in claim 2, An ultra-wideband radio frequency bidirectional coupler, wherein the second edge (240B) of the pair of opposing edges is formed as an arc, and the arc is the arc of a second circle having radius r2, and the center OB of the second circle is located closer to the first edge (240A) than to the second edge (240B).

4. The ultra-wideband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) according to claim 3, wherein the radius r1 and the radius r2 are equal.

5. In the ultra-wideband radio frequency bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) described in claim 1, It further has multiple protrusions, The plurality of protrusions are assigned to a first group of access ports (P-L1 to P-LM) and a second group of access ports (P-R1 to P-RN). Ultra-wideband radio frequency bidirectional coupler.

6. The dielectric waveguide structures (DW-L1 to DW-LM), (DW-R1 to DW-RN) are arranged on the free propagation region substrate (310) in the ultra-wideband radio frequency bidirectional coupler (300) according to claim 1.

7. The dielectric waveguide structures (DW-L1 to DW-LM), (DW-R1 to DW-RN) are embedded in the free propagation region substrate (310), as described in claim 1, for the ultra-wideband radio frequency bidirectional coupler (400A, 400B).

8. In the ultra-wideband radio frequency bidirectional coupler (200B, 300) according to claim 1, The dielectric waveguide structures (DW-L1 to DW-LM), (DW-R1 to DW-RN) are equipped with tapered ends having a defined DW taper shape, The first and second groups of the access ports (P-L1 to P-LM) and (P-R1 to P-RN) have a high cutoff frequency f in the millimeter wave range. ＣＨ It further includes tapered slot antennas (TSA-L1 to TSA-LM), (TSA-R1 to TSA-RN) that provide bandpass filter transfer functions operating over a low frequency range up to [a certain frequency], The aforementioned tapered slot antennas (TSA-L1 to TSA-LM), (TSA-R1 to TSA-RN) are equipped with a TSA tapered shape (300a, 300b, 300c), The first tapered ends of the dielectric waveguide structures (DW-L1 to DW-LM) and (DW-R1 to DW-RN) are located between the tapered slot antennas (TSA-L1 to TSA-LM) and (TSA-R1 to TSA-RN). The TSA taper shape (300a, 300b, 300c) matches the DW taper shape. Ultra-wideband radio frequency bidirectional coupler.

9. The ultra-wideband radio frequency bidirectional coupler (200B) according to claim 8, wherein the TSA tapered shape (300a) and the DW tapered shape are linearly tapered.

10. The ultra-wideband radio frequency bidirectional coupler (200B) according to claim 8, wherein the TSA taper shape (300b) and the DW taper shape are exponentially tapered.

11. The ultra-wideband radio frequency bidirectional coupler (200B) according to claim 8, wherein the TSA taper shape (300c) and the DW taper shape are Fermi tapered.

12. In the ultra-wideband bidirectional coupler (700) according to claim 8, Starting from a low frequency in the DC or kilohertz range, and the low cutoff frequency f in the millimeter wave range ＤＣＨ A low-frequency directional coupler (750) having an operating frequency range that reaches up to, Here f ＤＣＨ > Low cutoff frequency f of dielectric waveguide structure ＣＬ、 And, f ＣＨ Multiple transmission lines (720) and waveguide transitions connect the low-frequency directional coupler (750) and the tapered slot antennas (TSA-L1 to TSA-LM), (TSA-R1 to TSA-RN) to the combined operating frequency range up to, Furthermore, it is equipped with an ultra-wideband bidirectional coupler (700).

13. In the ultra-wideband bidirectional coupler (300) according to claim 6, Two first access ports (P-L1 to P-L3) along at least one edge of the free propagation region substrate (310) having first and third dielectric waveguide structures (DW-L1 to DW-L3) having tapered ends, Two second access ports (P-R4 to P-R2) along the opposite edge of the free propagation region substrate (310) having fourth and second dielectric waveguide structures (DW-R4 to DW-R2) with tapered ends, Equipped with, The tapered end of the first dielectric waveguide structure (DW-L1) points toward the tapered end of the second dielectric waveguide structure (DW-R2), The tapered end of the fourth dielectric waveguide structure (DW-R4) points toward the tapered end of the first dielectric waveguide structure (DW-L1), The tapered end of the third dielectric waveguide structure (DW-L3) points toward the tapered end of the second dielectric waveguide structure (DW-R2). Ultra-wideband bidirectional coupler (300).

14. In the ultra-wideband bidirectional coupler (300) according to claim 13, The first to fourth dielectric waveguide structures (DW-L1 to DW-L3), (DW-R2 to DW-R4) are equipped with a DW tapered shape. The high cutoff frequency f in the millimeter wave range ＣＨ It further includes metal tapered slot antennas (TSA-L1 to TSA-L3), (TSA-R2 to TSA-R4) that provide low-pass characteristic interconnects and operate over a low frequency range up to [a certain frequency]. The tapered slot antennas (TSA-L1 to TSA-L3), (TSA-R2 to TSA-R4) are provided with TSA tapered shapes (300a, 300b, 300c) around the first tapered end of the first to fourth dielectric waveguide structures (DW-L1 to DW-L3), (DW-R2 to DW-R4), The TSA taper shape (300a, 300b, 300c) matches the DW taper shape. Ultra-wideband bidirectional coupler (300).

15. The dielectric waveguide structures (DW-L1 to DW-LM), (DW-R1 to DW-RN) are provided with at least one truncated end, wherein the ultra-wideband radio frequency bidirectional coupler (400A, 400C) is according to claim 1.

16. The ultra-broadband bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) according to claim 1, wherein the free propagation region substrate (310) has a dielectric constant different from that of the dielectric waveguide structure (DW-L1 to DW-LM), (DW-R1 to DW-RN).

17. The ultra-broadband bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) according to claim 1, wherein the free propagation region substrate (310) comprises an absorber.

18. The ultra-broadband bidirectional coupler (400C) according to claim 1, wherein the free propagation region substrate (310) comprises a dielectric material.

19. In the ultra-wideband bidirectional coupler (200A, 200B, 300, 400A, 400B, 400C) described in claim 3, The radius r1 of the arc of the first circle for the first group of access ports (P-L1 to P-LM) is equal to the radius r2 of the arc of the second circle. The centers (OA, OB) of the two circles are aligned radially. Ultra-wideband bidirectional couplers (200A, 200B, 300, 400A, 400B, 400C).

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