777 results about "Directional coupling" patented technology

The invention discloses a calibration system in an active channel of a waveguide array phased-array antenna, and relates to the technical field of calibration in the active channel. Comprising a calibration judgment module, a waveguide directional coupling module, an amplitude-phase detection module and a digital domain optimization module, the calibration judgment module realizes intelligent triggering calibration through real-time monitoring of a multi-dimensional environment and performance parameters, and ensures that a calibration process is started only when the system state is deteriorated; the waveguide directional coupling module ensures that the calibration signal is accurately injected into each channel, and realizes cross polarization suppression through a polarization grid filter; the amplitude-phase detection module realizes high-precision measurement of amplitude, phase, group delay and polarization parameters of feedback signals of each channel by using superheterodyne and IQ demodulation technologies; and the digital domain optimization module calculates and updates the complex compensation weight of each channel through real-time digital signal processing and a self-adaptive algorithm, and realizes comprehensive and accurate calibration in combination with temperature-frequency interpolation and nonlinear pre-distortion compensation.

The invention discloses a response time conduction type testing device and method for a radio frequency channel protection device. The response time conduction type testing device comprises a transient field intensity generating device, an isolator, a directional coupler, a first attenuator, a second attenuator, a third attenuator, a first power meter, a second power meter, a high-speed oscilloscope, a vector network analyzer and a radio frequency channel protection device to be tested. According to the method, the response performance of the protection device under the influence of the transient strong field can be comprehensively, safely and accurately evaluated, the amplitude limiting function of the protection device can still be effectively exerted under the action of the transient strong field with an extremely narrow rising edge, and then subsequent devices, circuits and equipment are prevented from being damaged.

The invention discloses a millimeter wave broadband dual circularly polarized antenna and an array. The millimeter wave broadband dual circularly polarized antenna comprises two layers of microwave medium substrates, a bonding medium, a grounding metal plate and a coaxial feed probe. Two E-shaped patch antennas, four small square patches and an L-shaped metal strip are printed on the upper surface of the upper-layer dielectric substrate, gaps are obliquely formed in the centers of the small square patches, the L-shaped metal strip is used for increasing port isolation, and the E-shaped patches excite the four small square patches to achieve the broadband radiation characteristic. And two coaxial feed probes are respectively connected with two output ends with 90-degree phase difference of the 3dB directional coupler on the lower surface of the lower-layer microwave dielectric substrate, sequentially penetrate through the lower-layer microwave dielectric substrate, the bonding medium, the grounding metal plate and the upper-layer microwave dielectric substrate, and are electrically connected with the two E-shaped patch antennas, so that circularly polarized radiation is realized. According to the invention, the circularly polarized antenna with wide beam width, wide impedance bandwidth, wide axial ratio bandwidth and dual polarization characteristics is realized, and the circularly polarized antenna is suitable for potential application requirements of millimeter wave frequency band wireless communication and satellite communication.

The invention discloses a Ka-band waveguide three-way power divider, which belongs to the technical field of microwave and millimeter waves, and is characterized in that a combining port is formed in the front side wall of a shielding box, and three distribution ports are formed in the rear side wall of the shielding box; a coplanar magic T equal power divider, a coplanar magic T equal power combiner, a branch waveguide unequal power divider, an L-shaped waveguide, a Z-shaped waveguide and a half waveguide-full waveguide gradual change structure are arranged in the shielding box. Wherein the coplanar magic T equal power divider comprises an E-T junction waveguide cavity, two equal branch waveguide cavities, a microstrip probe and a power resistance load, and outputs two paths of signals with equal amplitude and opposite phases; the branch waveguide unequal power divider comprises a four-branch waveguide directional coupler and an inclined-wedge-shaped waveguide matching load, and the output power ratio of a straight-through output port to a coupling output port is 2: 1. The filter has the advantages of being symmetrical in structure, good in amplitude and phase consistency, small in insertion loss, good in port standing wave and high in isolation degree.

The invention discloses a high-gain wide-beam telemetering ground receiving antenna based on a multi-array-element structure, which comprises an antenna array, a metal floor and an array base, and is characterized in that the antenna array adopts the multi-array-element structure and comprises eight antenna units; each antenna unit comprises a parasitic layer, a micro-strip antenna layer, a feed network layer and a metal cylindrical cavity structure, the parasitic layer, the micro-strip antenna layer, the feed network layer and the metal cylindrical cavity structure are sequentially supported, assembled and connected by medium supporting columns from top to bottom, and the feed network layer adopts a branch line directional coupler in a micro-strip form. According to the high-gain wide-beam telemetering ground receiving antenna based on the multi-array-element structure, the bandwidth of the microstrip antenna is widened in a parasitic structure mode, and the impedance bandwidth of the antenna is widened by adjusting the parasitic size and height; a metal cylindrical cavity is reinforced on the bottom layer of the microstrip network so as to enhance the gain and the axial ratio of the microstrip.

The invention discloses an orthogonal directional coupler and a microwave system based on a micro-coaxial technology, the orthogonal directional coupler comprises a metal outer conductor, an upper inner conductor and a lower inner conductor, the upper inner conductor and the lower inner conductor are suspended in the metal outer conductor through a periodic medium support loading structure; the upper inner conductor and the lower inner conductor serve as two identical micro coaxial coupling lines to be cascaded, the micro coaxial coupling lines are symmetrical multi-stage impedance stepped couplers, each micro coaxial coupling line is provided with n coupling units, the coupler structure is symmetrical about the center coupling unit, the upper inner conductor and the lower inner conductor are overlapped in the axial direction at the center coupling unit, and the upper inner conductor and the lower inner conductor are overlapped in the axial direction at the center coupling unit. The upper inner conductor and the lower inner conductor extend from the center coupling unit to the two ends, the upper inner conductor and the lower inner conductor deviate from the center to the two sides, and the closer to the coupling units at the two ends, the larger the offset is; the ultra-wideband orthogonal antenna can work in the frequency range of 5 GHz to 100 GHz, the return loss is superior to 15 dB, the phase change is smaller than 5.5 degrees, the directivity is superior to 10 dB, and the ultra-wideband orthogonal antenna can be used for generating ultra-wideband orthogonal signals.

A device comprises a superconducting quantum circuit comprising a coupler which is coupled to a first quantum bit and a second quantum bit. The coupler comprises a tunable coupler and a fixed coupler. The coupler is configured to operate in a first mode to suppress coupling between the first quantum bit and the second quantum bit, when the tunable coupler is tuned to have a first frequency which corresponds to a fixed frequency of the fixed coupler. The coupler is configured to operate in a second mode to enable coupling between the first quantum bit and the second quantum bit, when the tunable coupler is tuned to have a second frequency which is different from the fixed frequency of the fixed coupler.

The invention relates to a circularly polarized quasi-absorption filtering phased-array antenna. A unit of the antenna comprises a multi-layer dielectric substrate, a semi-cured layer, a metal floor, a stacked patch and an orthogonal H-shaped gap, the first dielectric substrate is provided with a parasitic square loop, the second dielectric substrate is provided with a cross-shaped strip, and radiation zero points are introduced to the upper and lower edges of a passband respectively; the 3dB orthogonal directional coupler and the L-shaped feeder form a feed network, circularly polarized radiation is realized through slot coupling, and an isolation port of the 3dB orthogonal directional coupler is connected with a 50-ohm resistor, so that the energy of a lower stop band is absorbed, the energy of an upper stop band is reflected, and a quasi-absorption filtering characteristic is presented; the antenna is compact in structure and easy to process, has wide axial ratio bandwidth and good filtering performance, and when array scanning is 0-45 degrees, the overlapping impedance bandwidth is 12%, the axial ratio bandwidth is 15.8%, and the maximum scanning loss is 2.3 dB; the antenna is compact in structure and easy to process, has wide axial ratio bandwidth and good quasi-absorption filtering performance, and has huge potential in millimeter wave satellite communication application.

The invention relates to the technical field of radio frequency generator circuits, and provides a phase-locking frequency-stabilizing multi-core control radio frequency system, which processes I / Q signals and constructs a multi-core task allocation and cooperation mechanism through a digital baseband processing module, and performs pre-distortion processing and system scheduling. The double-closed-loop control module is used for stabilizing fundamental frequency, correcting temperature drift and compensating and adjusting frequency swing amplitude; the hybrid power amplification module is used for performing multi-stage hybrid power amplification signal processing and temperature monitoring through a driving stage and output stage combined topology; and the feedback sampling network module collects output signals in real time through a directional coupler and feeds back, adjusts and precisely controls the frequency stability according to the output signals.

A base station antenna includes a calibration circuit that has a plurality of pairs of directional couplers and an antenna array that includes a plurality of columns of radiating elements. The first polarization radiators of the radiating elements in each column are electrically connected to a first directional coupler of a respective one of the pairs, and the second polarization radiators of the radiating elements in the column are electrically connected to a second directional coupler of the respective one of the pairs. The directional couplers may be arranged in a manner that reduces in-column coupling and / or that reduces cross-column coupling between adjacent columns of radiating elements.

The utility model provides a directional coupler and a radio frequency chip, and relates to the technical field of electronic communication. The directional coupler comprises an input port, an output port, a coupling port, an isolation port and an impedance adjusting network, the impedance adjusting network comprises an access switch, an impedance adjusting module and an inductance unit. The impedance adjusting module comprises an adjustable resistor unit and an adjustable capacitor unit which are connected in parallel; one end of the impedance adjusting module is connected to the isolation port through the access switch, and the other end of the impedance adjusting module is connected to the inductance unit; wherein the inductance unit is used for compensating parasitic capacitance in the directional coupler. According to the scheme, the impedance matching and phase characteristics of the directional coupler can be adjusted according to different working frequencies and environmental conditions through mutual cooperation of the access switch, the impedance adjusting module and the inductance unit, so that the directional coupler can maintain good directivity under various working conditions.

The invention discloses a microwave reflectometer system. An arbitrary waveform generator generates a microwave signal through an X-Ku signal source unit; the coaxial directional coupler divides the generated microwave signal into two paths, one path enters the transmitting unit, and the other path enters the reference unit; a microwave signal entering the transmitting unit is transmitted into the plasma through a fundamental mode rectangular waveguide in the transmitting circuit; the microwave signal entering the reference unit is subjected to flight time compensation through a delay line and then is mixed with a reflected signal received by the receiving unit in a balanced mixer; the calibration unit carries out secondary frequency mixing on the dispersion calibration voltage-time curve signal and the signal obtained after primary frequency mixing of the balanced frequency mixer so as to eliminate dispersion interference; the acquisition card acquires an output signal after secondary frequency mixing of the calibration unit. The system can be integrated with an ion cyclotron resonance antenna, the inherent defects of large attenuation and high dispersion of a long-distance fundamental mode waveguide are overcome, and a high-frequency fundamental mode waveguide through-wall scheme meeting ultrahigh vacuum performance index requirements is realized.

The invention belongs to the technical field of integrated photoelectronics, and discloses a phase change photosynaptic device array and a preparation method thereof. The synaptic device array is of a cross array structure formed by a plurality of phase-change optical synaptic cells through directional couplers with the same number, an arc waveguide in each phase-change optical synaptic cell comprises a phase-change waveguide section, a heating layer is arranged above a phase-change material layer, and an isolating layer is arranged between a metal electrode and the waveguide. According to the synaptic device array, current joule heat generated by the heating layer under the action of electric pulses is transmitted to the phase-change material layer, so that the state of the phase-change material layer is changed, meanwhile, the isolation layer is used for shielding absorption and interference of the metal electrode on optical signals in the waveguide, and the optical loss of the array is reduced; therefore, the problem of heating structure integration of the phase-change photosynaptic device array can be effectively solved, and effective modulation of the phase-change photosynaptic device array is realized.

The invention relates to a construction method of a photon neural network, an image processing method, equipment and a medium, and the construction method comprises the steps: forming a silicon waveguide on a silicon-based substrate, periodically arranging phase change units on the surface of the silicon waveguide to form a two-dimensional array, and constructing a phase change metasurface with a beam splitting function by regulating and controlling the state of the phase change units. An input port and an output port are connected through a tapered waveguide to form an optical power beam splitter; output optical signals pass through a crossed waveguide and a directional coupler and are arranged according to a convolution kernel matrix structure, and a photon convolution kernel is constructed. A multi-wavelength laser source, an optical modulator and a photoelectric detector are integrated, the state of a phase change unit is dynamically regulated and controlled, and a photon neural network is established. And after matrix operation, the optical signal is converted into an electric signal by the photoelectric detector and is output to the processing module, so that the network performance is remarkably improved, and an efficient and low-energy-consumption scheme is provided for deep learning.

A measurement system includes a common port, the common port being connectable to a signal output of the device under test. The measurement system further includes a signal line being connected to the common port, wherein the signal line includes a first directional coupler portion and a second directional coupler portion. The measurement system further includes a signal processing circuit, wherein the signal processing circuit includes an IQ analysis circuit and an IQ synthesizer circuit. The IQ analysis circuit is connected with the common port via the first directional coupler portion so as to receive a forward-travelling signal from the common port. Further, a testing method of testing a device under test is described.

The invention discloses an amplitude-phase-adjustable microstrip line high-directional coupling structure and a multichannel coupler. The amplitude-phase-adjustable microstrip line high-directional coupling structure comprises a dielectric plate, and an input port, a transmission port, a coupling port and an isolation port which are arranged on the dielectric plate, the input port is connected with the transmission port through the microstrip line, and the transmission port is used for being connected with the antenna port; the coupling port is connected with the isolation port through the two-stage coupling passband; the coupling port is used for outputting a coupling signal; the length of the coupling part of the two stages of coupling passbands can be adjusted; and a phase regulator for regulating the phase is arranged between the two stages of coupling passbands. The phase difference is formed through the distance between two stages of coupling, the amplitude and the phase are adjusted, coupling output is achieved at a coupling port, high isolation is achieved at an isolation port, and the problem that due to the fact that upper and lower media of a microstrip line high-directionality coupler are not uniform, the phase velocities of odd and even modes in the microstrip coupler are different, and the directionality of the microstrip line high-directionality coupler is poor is effectively solved. And the directivity is poor.

Example directional couplers and devices including one or more directional couplers are disclosed. In an example, a directional coupler comprises a first electrically conductive portion and a second electrically conductive portion, a first ground plane electrical conductor disposed in a plane between the first electrically conductive portion and the second electrically conductive portion, and a second ground plane electrical conductor and a third ground plane electrical conductor disposed such that the first and second electrically conductive portions and the first ground plane electrical conductor are between the second and third ground plane electrical conductors. The first ground plane electrical conductor includes at least one hole directly between the first electrically conductive portion and the second electrically conductive portion.

The invention discloses a broadband dual-circularly-polarized low-cost phased-array antenna array element, which comprises an antenna radiation structure and a slot feed structure which are arranged independently from each other, and is characterized in that the antenna radiation structure comprises a parasitic radiation layer, a first dielectric substrate, an excitation radiation layer and a second dielectric substrate which are arranged in a laminated manner; the slot feed structure comprises a slot layer, a third dielectric substrate, a strip-shaped transmission line and a fourth dielectric substrate; the antenna layer structure and the slot feed structure realize electromagnetic coupling transmission through the slot layer; a hollow symmetrical structure is arranged in the middle of the first dielectric substrate, and the hollow part is used as an air medium to reduce dielectric loss; the gap layer is provided with a multidirectional coupling gap structure; the strip-shaped transmission line is provided with at least two feed ports, and dual circularly polarized radiation is formed in the antenna layer structure through excitation of different feed ports. The antenna radiation layer has no metal through hole or blind hole, can be processed in a layered manner, has the advantages of low processing cost and high yield, and ensures impedance bandwidth while realizing dual circular polarization.

The invention discloses a broadband integrated polarization rotation beam splitter based on a complex linear gradient structure, which belongs to the technical field of integrated optical devices and comprises a substrate layer and a dielectric waveguide layer. A buried oxide layer is arranged between the substrate layer and the dielectric waveguide layer, upper cladding layers are arranged on the upper surface and two sides of the dielectric waveguide layer, and an input spot size converter, a mode evolver, a directional coupler and two output spot size converters are etched in the dielectric waveguide layer along the light wave transmission direction; and a bent waveguide is etched between the directional coupler and the first output spot size converter. The mode evolution effect and the mode hybridization phenomenon are utilized, the linear structure of the mode evolver is designed, the mode evolution efficiency is improved, separation of a TM0 component and a TE0 component in input light is achieved, the TM0 component is rotated, and pure TE0 light is obtained.

The invention discloses a high-performance dynamic routing circuit for improving S parameter measurement and a multi-port expansion box, and relates to an S parameter test and port expansion technology. The routing circuit applied to the transmitting path comprises four output ends, six transmitting branch port input ends, a transmitting total port input end, four first-stage equalization amplifiers, two first-stage one-to-two switches, two second-stage equalization amplifiers, four first-stage one-to-three switches, a first-stage one-to-four switch and a third-stage equalization amplifier. The internal paths of the circuit are symmetrical, and the transmission path length of signal routing gating is minimized through the arrangement of a total port and branch ports, so that high performance is ensured. The multi-port expansion box comprises a routing circuit applied to a transmitting path, a routing circuit applied to a reference / test receiving path, a transmitting / reference receiving / test receiving standard configuration routing amplification unit, a bi-directional coupler matrix and the like. Port expansion can be flexibly configured and high performance can be ensured.

Disclosed is a device including a first line, a second line including a first section disposed on a first side of the first line and a second section disposed on a second side of the first line, the second side being opposite to the first side and the second section being separate from the first section by a distance, and at least one bridge electrically connecting an end of the first section with an end of the second section and extending across the first line. The device may be a directional coupler that achieves significantly higher directivity than conventional directional coupler structures, and hence, improves power detection accuracy.

The embodiment of the invention provides a radio frequency circuit and electronic equipment, and the radio frequency circuit comprises a radio frequency signal link which is connected with an antenna end and is used for transmitting a radio frequency signal of a radio frequency input end to the antenna end or receiving the radio frequency signal from the antenna end; the bi-directional coupler performs forward power detection and reverse power detection on the radio frequency signal on the radio frequency signal link to generate a forward power value and a reverse power value; the VSWR calculation network circuit is used for calculating a ratio between the forward power value and the reverse power value to obtain a power ratio; outputting a protection control signal based on the power ratio and a preset VSWR threshold value; the power limiting network control circuit receives the protection control signal and outputs a pull-down control signal based on the protection control signal; a plurality of power limiting networks, wherein each power limiting network is connected with the radio frequency signal link; and the power limiting networks are used for receiving the corresponding pull-down control signals and carrying out power pull-down on the radio frequency signals in the radio frequency signal link based on the pull-down control signals.

The invention discloses a calibration system and a calibration method of a directional coupler. The system comprises an input end assembly, a front-end monitoring assembly and a rear-end measuring assembly which are connected in sequence, the front-end monitoring assembly comprises a first directional coupler, a first power meter and a first matching load; the bandwidth of the first directional coupler comprises the frequency of a microwave signal source to be calibrated and the frequency of a corresponding first harmonic, and the frequency of a second harmonic corresponding to the frequency is outside the bandwidth of the first directional coupler; the rear-end measurement assembly comprises a second directional coupler, a second power meter, a second matching load and a high-power matching load, wherein the second directional coupler is provided with a reference directional coupler and a calibration directional coupler which are used for replacement; the bandwidth of the reference directional coupler is the same as that of the first directional coupler; the bandwidth of the directional coupler for calibration comprises the frequency of the microwave signal source to be calibrated but does not comprise the frequency of the first harmonic corresponding to the frequency, and a calibration factor is determined based on the reading of the power meter.

The invention discloses a BTM power amplifier output fault diagnosis method and system, and relates to the technical field of fault detection, and the method comprises the steps: receiving and outputting a radio frequency energy signal through a directional coupler, and extracting a coupling voltage and a reflection voltage through the directional coupler; calculating a coupling voltage value and a reflection voltage value; judging a parameter interval where the coupling voltage value and the reflection voltage value are located; reporting a fault state detection result; wherein data in different fault states are collected for clustering integration, and a fault state judgment parameter interval conforming to field actual operation is extracted. The directional coupler, the processor, the communication module and other circuit modules are added on the basis of original power amplifier board card hardware, power amplifier output detection is carried out, the structure is simple, and a rapid and effective judgment basis is provided for rapid positioning and troubleshooting of electric service personnel.

The invention discloses a calibration factor estimation and correction method for a radio frequency high-power calibration direct measurement method, which comprises the following steps of: receiving a radio frequency high-power signal, and calculating an equivalent source reflection coefficient of a directional coupler to be corrected; arranging the test end face between the directional coupler and the DUT to detect a loss constant ka; estimation of the calibration factor of the direct measurement method is corrected through a radio frequency high-power standard indicating value measured through an experiment and a power indicating value of the DUT. According to the method, the situation that the error of the calibration factor of a direct measurement method is large at a high frequency is avoided, and the measurement error caused by the high frequency is reduced, so that the high-power measurement accuracy of the radio frequency directional power sensor in a high-frequency environment is improved.

The invention provides a heterogeneous integrated sub-wavelength structure end face coupler adaptive to a single-mode optical fiber and a preparation method of the heterogeneous integrated sub-wavelength structure end face coupler, and relates to the technical field of integrated optics. The coupler comprises a substrate, an insulating layer, a waveguide layer and a cladding from bottom to top. The waveguide layer comprises an upper lithium niobate ridge waveguide and a lower lithium niobate ridge waveguide, the lower waveguide is wider than the upper waveguide, and the upper waveguide is used for connecting an external waveguide; the heterogeneous integrated coupling region comprises a silicon nitride strip conical waveguide which forms directional coupling with the lower-layer lithium niobate waveguide, so that adiabatic transfer of a light field is realized; the sub-wavelength grating regulation and control region sequentially comprises a silicon nitride tapered waveguide and sub-wavelength grating combination section, a width gradually-changing grating section and an equal-width buffer grating section. The whole structure is symmetrical about the central axis. Through the multi-section adiabatic transformation and heterogeneous integration design, efficient expansion of a mode field is achieved, the coupling efficiency with a single-mode fiber is improved, and the advantages of being insensitive to polarization, good in process compatibility and suitable for high-density integration are achieved.

The invention relates to a terahertz high-power power amplifier assembly, which belongs to the field of electronic devices and comprises a synthesis network consisting of a synthesis network upper cavity and a synthesis network lower cavity, and a small signal amplification module, a medium-power amplification module, a driving-stage power amplifier module, a final-stage power amplifier module and a detection module are arranged on the back surface of the synthesis network lower cavity. An E-plane waveguide directional coupler is arranged in the synthesis network, the small signal amplification module, the medium-power amplification module, the driving-stage power amplification module, the final-stage power amplification module and the E-plane waveguide directional coupler are electrically connected in sequence, and a port of the E-plane waveguide directional coupler is electrically connected with the detection module; a waveguide tube is arranged in the installation position of each module in the synthesis network, and the modules are electrically connected through the waveguide tubes. According to the invention, each stage of amplifier is modularly designed, so that the isolation degree among devices of a link can be increased, and the self-excitation risk caused by space radiation is reduced. And the testability of a single module is improved, and the troubleshooting cost and time are reduced.

A waveguide apparatus, associated components and methods. The waveguide device may include a rectangular waveguide having a first rectangular port and a second rectangular port at one end, and a first circular waveguide and a second circular waveguide extending from a broad side opposite the waveguide to provide full isolation or full transmission between the first port and the second port. The waveguides may include a fixed short circuit at one circular waveguide and a short circuit with an adjustable bias structure at the other circular waveguide to accommodate a wider range of high power capabilities. The waveguide devices may be stacked by connecting circular waveguides of adjacent structures to provide an isolator with additional ports or adjustable directional couplers. The adjustable shorting structure may include a plunger or a helical thread. The waveguide may include a rectangular waveguide in a four-port network in which the circular waveguide extends to a fifth port supporting two modes of operation and may be shorted by a contoured disk of non-reciprocal material.

The invention provides a calibration network and an antenna system, and relates to the technical field of antenna communication, the calibration network comprises a power divider, and an oscillation circuit and a plurality of directional couplers which are connected with the power divider; the power divider comprises a first port and a plurality of second ports; the oscillating circuit is connected to the first port; the directional couplers are connected to the corresponding second ports; the oscillating circuit is connected with the antenna driver to protect the antenna driver; the directional coupler comprises a coupling part and a connecting port connected with the coupling part, and the connecting port is used for being connected with an antenna; wherein the coupling part of each directional coupler is provided with a short-circuit wire, one end of the short-circuit wire is connected with the coupling part, the other end of the short-circuit wire is grounded, and the short-circuit wire is used for protecting the circuit of the antenna. According to the calibration network and the antenna system provided by the invention, the antenna can be kept stable in extreme weather such as high-power radiation of a user in a peak period or thunderstorm, so that the communication quality of the antenna is ensured.

The invention relates to a strip line short section directional coupler, relates to the technical field of communication, and is used for improving the directivity of the strip line short section directional coupler. The strip line short section directional coupler comprises a radio frequency main line, a strip line coupling circuit and a capacitance compensation circuit, the strip line coupling circuit comprises a coupling line, two beveled edge corners and two vertical lead-out strip lines, two ends of the coupling line are respectively connected with one end of one beveled edge corner, and the other end of the beveled edge corner is connected with one end of one vertical lead-out strip line; the radio frequency main line comprises an input end, a coupling main line and an output end, and the coupling main line and the coupling line are coplanar and parallel to each other; the capacitance compensation circuit comprises a metal cylinder group which is connected with an upper-layer ground wire and a lower-layer ground wire of the strip line coupling circuit, and the metal cylinder group is located on the outer side of the bevel cut edges of the two bevel cut edge corners at the two ends of the coupling line and is in bilateral symmetry about the perpendicular bisector.