370 results about "Relative bandwidth" patented technology

A method is provided for allocating bandwidth to a subscriber in a service provider domain that is part of a packet switched network such as the Internet, for example. In accordance with the method, a number of shares of bandwidth are assigned to the subscriber based on an agreement between the subscriber and a service provider. A subscriber identifier and the number of shares assigned thereto are distributed to the routers in the domain of the service provider. The routers will in turn allocate bandwidth to packets they receive based on the number of shares assigned to the subscriber transmitting or receiving the packet. The subscriber may include one or more different user terminals that aggregate traffic onto a single datastream. The shares assigned to the user may denote absolute amount of bandwidth, or alternatively, may denote a relative bandwidth allocation.

The invention discloses a novel broadband printed dipole antenna with a branch wire integrated with a feed balun. The novel broadband printed dipole antenna comprises an SMA (Shape Memory Alloy) joint, a dielectric-slab, a radiating element and a microstrip line feed integrated balun, wherein the radiating element is provided with a slotting seam; dual radiation arms are formed on both sides of the slotting seam; the microstrip line feed integrated balun is provided with a branch wire; the branch wire is equivalent to a series resistor, and is used for improving the matched impedance. According to the novel broadband printed dipole antenna, the VSWR (Voltage Standing Wave Ratio) is less than or equal to 1.5, and the relative bandwidth is up to 58.7 percent (1.65-3.0GHz); compared with other bandwidth extension technologies (such as a parasitic patch increasing technology), the novel broadband printed dipole antenna has the advantages that design is made on the basis of not changing the original size of the antenna, so that the bandwidth of the antenna is improved, other performance of the antenna (such as gain and cross polarization level) is not influenced, and the occupied space is reduced; the novel broadband printed dipole antenna has the advantages of simple structure, convenience, practicability, wide adaptability and the like.

Techniques are disclosed for providing a bandwidth control interface that displays the relative amount of bandwidth assigned to each application executing at a computer device. By displaying the relative amount of bandwidth, the interface allows the user to easily determine how the available bandwidth is allocated among the applications, and whether the allocation provides for efficient network communication. The bandwidth control interface also allows the user to adjust the relative allocation of bandwidth to the executing applications. The user can thereby control the relative amount of bandwidth that is allocated to each application by a network interface device.

Various resonant modes of a multiresonant antenna structure share at least portions of the structure volume. The basic antenna element has a substantially planar structure with a planar conductor and a pair of parallel elongated conductors, each having a first end electrically connected to the planar conductor. Additional elements may be coupled to the basic element in an array. In this way, individual antenna structures share common elements and volumes, thereby increasing the ratio of relative bandwidth to volume.

The invention provides a non-sinusoidal time domain orthogonal modulation method which is non-sinusoidal wave modulation based on orthogonal pulse transmission information. Signals to be transmitted are modulated onto a time domain orthogonal impulse group and impulse parameters are regulated to realize the spectrum shifting and the spectrum control of the modulated signals. The modulated signals are band-limited signals, the spectrum characteristic of which can be controlled. The modulated signals can be applied to any communication frequency band. Communication with relative large bandwidth or broadband communication can be realized, and communication with relative small bandwidth or narrowband communication can be realized. In spectrum management, the method can be compatible with an existing frequency band-division and channel-division communication mode of a relative small bandwidth communication system. And the frequency band utilization rate of the system can infinitely approach Nyquist rate with the increase of orthogonal impulses.

The invention discloses an ultra-wideband (UWB) filter with band-notched characteristics. The UWB filter comprises a metal microstrip line at a front face part, a metal coating at a rear face part and a dielectric slab at a middle layer, wherein, the metal microstrip line is of a linear cascaded microstrip line structure which is formed by alternately connecting comb coupled microstrip lines with a quarter of wavelength and a microstrip line with half wavelength; the microstrip line with half wavelength is provided with microstrip slits; uniform transmission parts on the outer ends of the two comb coupled microstrip lines are respectively and electrically connected with input and output interfaces and two short-circuit stubs with a quarter of wavelength; and free ends of the short-circuit stubs with a quarter of wavelength are electrically connected with the metal coating at the rear face part. The UWB filter disclosed by the invention has the advantages of good band-notched characteristics, high coupling coefficient, small volume, easy machining process, steep sideband characteristics and good frequency selectivity, and a passband is internally provided with a steep trap with the relative width of more than 125%, thus meeting the requirement for miniaturization.

The invention discloses a balanced radio frequency electrically tunable bandpass filter with constant relative bandwidth. The bandpass filter consists of an upper-layer microstrip structure, a middle-layer dielectric substrate, and a lower-layer grounded metal. The upper-layer microstrip structure is a balanced circuit, and comprises four half-wavelength resonators, two input feed networks, two output feed networks, two input ports and two output ports; the four half-wavelength resonators respectively consist of microstrip lines and variable capacitance diodes connected at two ends; the middle of the first half-wavelength resonator is connected with a capacitor and a microstrip line; the middle of the third half-wavelength resonator is connected with a capacitor; the second and fourth half-wavelength resonators are bent and symmetrical vertically; and the whole filter structure is in vertical mirror symmetry. The balanced radio frequency electrically tunable bandpass filter realizes constant relative bandwidth when a center frequency is tuned, can inhibit common-mode interference and can be used for a reconfigurable radio frequency front end for wireless communication.

The invention discloses a broadband multi-polarized reconfigurable slot antenna and a polarization method therefor. The broadband multi-polarized reconfigurable slot antenna comprises four layers of dielectric substrates, wherein an elliptical metal patch is arranged on the lower surface of the first layer of dielectric substrate; a first feed structure is arranged on the upper surface of the second layer of dielectric substrate; a metal layer is arranged on the upper surface of the third layer of dielectric substrate; a quasi-cross-shaped slot is formed in the metal layer; a second feed structure is arranged on the upper surface of the fourth layer of dielectric substrate; and a reconfigurable wilkinson power divider is arranged on the lower surface of the fourth layer of dielectric substrate. The linear polarization radiation state with ultrahigh port isolation in two vertical directions can be achieved through a quasi-cross-shaped slot antenna fed through the first feed structure and the second feed structure; the wilkinson power divider conducts different paths through pin diodes and is connected with the first feed structure and the second feed structure through a plated through hole, so that five different antenna polarization modes of -45-degree linear polarization, 45-degree linear polarization, +/-45-degree dual-linear polarization, left-hand circular polarization andright-hand circular polarization can be achieved, the relative bandwidth is close to 20%, and the broadband multi-polarized reconfigurable slot antenna fully adapts to different work requirements.

Following three functions are integrated to synthesize a basic antenna feeder line unit: balanced dipole of possessing radiation function; Balun capable of restricting skin current of asymmetric transmission line (TL); strip TL for feeding power to dipole. The unit includes left/right radiation arms, left/right support plates, and feeding metal conduction band positioned between support plates. Connecting to any one arm, the metal conduction band accomplishes feeding power. The unit is connected to main TL under ground plate. It is symmetrical geometry arrangement related to symmetrical vibrator center so as to realize perfect current balance on two arms, and reach broadband performance of impedance and directional diagram. Features are: low cost; within 23.7% relative bandwidth, VSWR smaller than or equal to 1.4, G about 9dBi; broadband base station antenna produced from two kinds of size can cover CDMA/GSM, all 3G international standard in 806-960MHz and 1710-2170MHz.

The invention discloses a wide-band RCS reduction super surface based on slit loading, comprising a dielectric substrate, a metal patch for loading a gap and a metal floor. The metal patch loaded witha plurality of pairs of cross-shaped slits is printed on the upper surface of the dielectric substrate, and the metal floor is printed on the lower surface of the dielectric substrate. An artificialmagnetic conductor unit is designed to have a resonant frequency of 12 GHz, and the in-phase reflection relative bandwidth is 50%. At the same time, broadband AMC super units and double-ring AMC superunits are arranged according to a 3*3 chessboard manner at intervals. Each kind of AMC super units consists of 3*3 basic AMC units, and finally RCS reduction of 7.5 dB or more in the frequency rangeof 8 to 19.2 GHz is realized. The artificial magnetic conductor structure and the AMC-AMC checssboard-shaped electromagnetic stealth surface of the invention have the advantages of good robustness, polarization insensitivity and the like.

The invention discloses an X-band high-gain broadband lens antenna based on a phase gradient multilayer super-surface structure. The antenna exhibits a broadband characteristic by using a microstrip antenna based on H-type slot coupling as a feed source. Furthermore, a super-surface structural unit having a phase gradient variation feature is designed and arranged in accordance with a parabolic focusing equation. Therefore, good low profile characteristics are obtained. A combined super-surface transmission array can convert a normally incident quasi-spherical wave into a plane wave, thereby obtaining a high-gain antenna. The lens antenna operates in the X-band with a center frequency of 10 GHz and the relative bandwidth reaches 20.6%. The antenna gain can be increased from 8.25 dB to 18.98 dB, and the side-lobe level of the super-surface focusing is less than -14.3dB. The simple three-dimensional structure and compact size provide a new method for implementing high-gain antennas, andthe antenna is good in application prospect in field of long-distance wireless communication.

The invention relates to a design method of a low-profile dual-polarized tile antenna unit adopting T-shaped microstrip feeding. The design method is characterized in that an antenna patch unit adopts a T-shaped microstrip line for coupled feeding, a feeding network and the patch unit are located in one layer, and two polarizing and feeding networks are arranged; and a parasitic unit is located just above an excitation unit. The antenna has capability of suppressing antenna system low-frequency signal interference, and has standing wave ratio smaller than 1.8 and cross polarization level smaller than -17dB in 20% relative bandwidth; and the T-shaped microstrip line is adopted for coupled feeding as well as is located in one plane with an antenna radiation unit, thus the thickness of the antenna unit is significantly reduced. The obtained antenna unit not only can be used as a unit of a tile type array antenna, but also can be independently used as a transceiver antenna of a polarization diversity system.

Disclosed is an ultra-wideband power divider based on an exponential gradient. The ultra-wideband power divider is composed of microstrip lines and ports of the microstrip lines, wherein the microstrip lines are located on a dielectric slab and used as a power divider body, and achieve matching and transmission characteristic transformation. The ultra-wideband power divider is provided with one input port, two equi-amplitude and in-phase output ports, an impedance conversion circuit and an ultra-wideband power distribution circuit, wherein the impedance conversion circuit and the ultra-wideband power distribution circuit are located between the input port and the output ports. The characteristic impedance of each of the microstrip lines of the three ports is 50omega, and the whole circuits are vertically symmetrical. One microstrip line based on the exponential gradient is adopted for the input port, the microstrip line with a characteristic impedance of 50omega is matched to an input end of the ultra-wideband power distribution circuit, the microstrip lines with a characteristic impedance of 25omega are divided into two vertically-symmetrical output paths, four sections of semicircular microstrip lines are in cascade connection to output equi-amplitude and in-phase signals, the characteristic impedance of each section of semicircular microstrip line is 50omega, the electrical length of each section of semicircular microstrip line is pi/2, an isolating resistor is connected between each pair of microstrip lines arranged up and down, and the isolating resistors are different from one another. The ultra-wideband power divider based on the exponential gradient is good in transmission performance, and relative bandwidth can reach more than 100%.

The invention discloses a broadband high-efficiency Doherty power amplifier and a design method thereof. The relative bandwidth of an existing Doherty power amplifier is usually limited to be 50% or below, and the performance is obviously degraded at the edge of a frequency band. The broadband high-efficiency Doherty power amplifier comprises a power divider, a carrier power amplifying circuit, apeak power amplifying circuit, a post-matching network and an output resistor. The carrier power amplifying circuit comprises a carrier input matching network, a carrier power amplifier, a carrier output fundamental wave matching network and a carrier power amplifier compensation line. The peak power amplifying circuit comprises a peak value input matching network, a peak power amplifier, a peak value output fundamental wave matching network and a peak power amplifier compensation line. The post-matching network comprises a first micro-strip line, a second micro-strip line, a third micro-stripline, a fourth micro-strip line, a fifth micro-strip line and a sixth micro-strip line. The broadband high-efficiency Doherty power amplifier eliminates the bandwidth limit caused by a high-order matching network.

The invention relates to a small broadband substrate integrated waveguide planar magic-T structure, which comprises an upper layer of metal surface, a middle layer of metal surface and a lower layer of metal surface of a dielectric substrate. The dielectric substrate is provided with two rows of parallel metal posts, and a slot line structure etched out from the middle layer of metal surface so as to greatly realize the energy transmission from a microstrip line to substrate integrated waveguide (SIW). The adopted equal power division network of the substrate integrated waveguide (SIW) replaces the traditional branch structure, so that the volume of the whole planar magic-T structure is decreased to a half of the volume of the past substrate integrated waveguide (SIW) planar magic-T structure, the relative bandwidth of work of the magic-T is greatly increased, and the planar magic-T structure has good isolation characteristics with a difference arm and an equal power division port. The small broadband substrate integrated waveguide (SIW) planar magic-T has simple design, small volume and good electrical property and is easy to be integrated with other planar microwave millimeter wave circuits.

The invention provides a piezoelectric filter which comprises a signal line, at least one first resonator, at least one second resonator and at least one grounding branch. The signal line is used for connecting an input ending opening and an output end opening of the piezoelectric filter. The first resonators are connected to the signal line in series. The second resonators are connected to the signal line in parallel. Nodes on the signal lines are grounded through inductance by means of the grounding branches. By means of the piezoelectric filter, the relative bandwidth of the piezoelectric filter can be expanded effectively on the premise that the performance of the piezoelectric filter is not affected and even improved.

An FMCW type radar level gauge configured to transmit an electromagnetic transmit signal and receive an electromagnetic return signal reflected from the surface, the electromagnetic transmit signal having a bandwidth of at least 1 GHz, a relative bandwidth (max frequency/min frequency) of less than 2.5 and an upper frequency limit less than 4 GHz. The gauge comprises a single conductor probe mechanically suspended in the tank and extending into the product in the tank, and a matching arrangement providing an electrically matched connection between an electrical feed-through and the single conductor probe.

According to the present invention, the relatively expensive still-pipe is replaced with a relatively inexpensive a single conductor acting as a surface wave-guide (SWG).

The invention relates to a dual-layer patch dual-frequency disc microstrip antenna. The microstrip antenna discloses an upper layer part and a lower layer part, wherein the upper layer part comprises a first dielectric substrate and a metal patch located at the upper surface of the first dielectric substrate; the first dielectric substrate and the metal patch are round and have the same radius; the center of the metal patch is overlapped with the center of the first dielectric substrate; the lower layer part includes a second dielectric substrate, a grooved round patch located at the upper surface of the second dielectric substrate, as well as a metal grounding plate which is located at the lower surface of the second dielectric substrate, and a coaxial line; the second dielectric substrate is round; the center of the second dielectric substrate is overlapped with the center of the grooved round patch; a feed hole of the coaxial line is formed at the center of the second dielectric substrate; and the feeding mode of the antenna is a coaxial feed mode. According to the antenna, two resonant points can be excited, so that the relative bandwidth of the antenna can reach 19% or higher, and therefore, the working bandwidth of the antenna can be improved.

The invention is applicable to the field of radio frequency communication, and provides a harmonic power amplifying circuit with high efficiency and a wide bandwidth and a radio frequency power amplifier. The circuit comprises an input matching network, a transistor and an output matching network; a grid electrode of the transistor is connected with an output end of the input matching network, a drain electrode of the transistor is connected with an input end of the output matching network, and a source electrode of the transistor is grounded; the output matching network causes a lower sideband of the harmonic power amplifying circuit to work in a continuous inverse F amplification mode and causes an upper sideband of the harmonic power amplifying circuit to work in a continuous F amplification mode; and the output matching network and a parasitic network of the transistor form a low pass filter. According to the harmonic power amplifying circuit provided by the invention, due to the transition from the continuous inverse F power amplifier working mode to the continuous F power amplifier working mode, the efficiency of a continuous harmonic control power amplifier is effectively improved to be higher than 60%, a relative bandwidth is improved to be higher than 80%, and the harmonic impedance is simple to match and easy to realize.

The invention is concerned with broadband low loss switch filter group of surface acoustic wave. The group relates to tow groups of multi-throw switch with one knife and some filters of surface acoustic wave. One group switch joins up the imports of some filters of surface acoustic wave, the other group joins up the fan-outs of some filters of surface acoustic wave and the tow groups of switch is corresponding to each other. The structure to said filter of surface acoustic wave is longitudinal coupling resonant to realize the low loss. Different channels adopt some different longitudinal coupling structure to get as same bandwidth as possible for each channel. The base plate is LiNbO3, LiTaO_3, and so on. This invention affords a kind of switch filter group of surface acoustic wave for broad band to communications system (single channel relative bandwidth is 2%-7.3%), low loss (containing the switch, less than 6.5dB) and higher stop-band limit (more than 40 dB ).

The invention discloses a double-frequency combiner with high relative bandwidth, which comprises a band rejection filter arranged on a chamber and used for enabling ultra wide band signals to pass and a band filter used for enabling relative narrow band signals to pass. The band rejection filter comprises a conduction band. The band filter comprises a plurality of harmonic oscillation columns. After the band rejection filter is combined with the band filter, the signals are output through a common port. A combination part is arranged on the harmonic oscillation column of the band filter close to the common port. The combination part is coupled with the conduction band by means of slot coupling to couple signals between the two filters. The double-frequency combiner with high relative bandwidth widens the range of use of the combiner, and overcomes the limitation that the conventional combined can only be used in the mobile communication system; in addition, as sufficient gaps are reserved between the internal parts, the power capability is improved. Furthermore, the invention has the advantages of high electric indices, low cost, simple process and the like.

The present invention discloses a wide-band backfire spiral antenna, including a feeder module (1), a primary radiator and a reflection cavity. The feeder module (1) consists of a connecting column (11), a transitional feeding medium (12), a conversion feeding medium (13), an external feeding conductor (14), an internal feeding conductor (15), a cable (16) and an electric connector (17), which are connected accordingly. The primary radiator is formed by winding a metal spiral wire (5) on the medium support of the spiral wire (4). The reflection cavity includes a reflection tray (2) and a reflection cavity (3). The filing medium in a transforming feed medium (13) is air. The reflection cavity is the ode-shaped reflection cavity. The antenna of the invention can widen the bandwidth, and the relative bandwidth reaches to 30% above. And the antenna has the advantages of simple structure and good consistency. At the same time, a technique of combining the backfire spiral with the ode-shaped reflection cavity is adopted to improve the aperture utilization ration of the antenna. And the gain of the antenna reaches to 10dB above.

The invention discloses a tight coupling array antenna applied to a 5G communication system. By adoption of an interdigital dipole antenna array plate 10, a grid form resistive frequency selection surface plate 20, the multilayered structure of a grounding plate (GP) 30, and a tight coupling array, the problem that the antenna array is limited in the 5G frequency band impedance bandwidth and the influence on the antenna performance from the grounding plate (GP) 30 in the prior art are solved; a technical effect of small size and large bandwidth is realized; powerful support to the research of the 5G large-scale array antenna is supplied; the relative bandwidth of the antenna provided by the invention can reach 149.1%; and the active standing-wave ratio at the frequency band of 2.8-19.2GHz can satisfy a condition that Active VSWR is less than 3. The tight coupling array antenna can be widely applied to the design field of the 5G antenna.

The invention belongs to the technical field of stealth technology and radar antennas, and particularly relates to a broadband wide-angle frequency selective surface radome, which is formed by arranging a plurality of basic units in an array mode. Each basic unit comprises a first dielectric layer, a second dielectric layer, a frequency selective surface layer and a third dielectric layer, which are sequentially arranged. The dielectric layers are symmetrically loaded and form the Chebyshev impedance converter with the frequency selective surface layers, so that the problems of narrow wave-transparent frequency band, low wave-transparent rate and unstable angle of the radome are solved; meanwhile, the frequency selective surface layer is formed by utilizing the metamaterial design principle; the radome is formed by arranging the basic units periodically in the form of a square, and comprises a uniquely designed miniaturized sub-wavelength periodic pattern; and compared with a multi-layer radome loaded with a metal mesh, a multi-layer metamaterial surface coupling form and other forms of frequency selective surfaces, the radome is wider in high-wave-transmission relative bandwidth and wider in angle application range, and is simple in structure and low in cost.