50 results about "Axial mode" patented technology

A wind harnessing system using a plurality of self supporting airfoil kites 50 for production of useful power. The system comprising multiple airfoil kites 50 in tandem attached to a pivotal control housing 32 by control lines 58L and 58R and support lines 60L and 60R. Control lines 58L and 58R can change length with respect to the length of support lines 60L and 60R to control the airfoil kites' 50 angle-of-attack, pitch angle, direction of flight, and flight speed. The length of control lines 58L and 58R are controlled from ground station 30 by a movable pulley system in control housing 32 to adjust the airfoils' direction to follow a specific flight path 140. Control lines 58R and 58L and support lines 60R and 60L are also wound on a power shaft and pulley system in control housing 32. As the airfoil kites are propelled by the wind at very-high speed, the airfoils generate a powerful AXIAL force. The control lines 58L and 58R and support lines 60L and 60R are then reeled-out under this AXIAL tension causing the power shaft and pulley system in control housing 32 to turn a generator to generate electricity. After airfoil kites 50 have finished their reel-out power stroke 140a, the airfoil's pitch angle is made negative so they can be reeled-in by their control and support lines using a minimum of force along path 140b. Once the airfoils have been rewound to the proper distance, the airfoils are again angled for high-speed operation to generate powerful AXIAL force and reeled-out along 140c to provide another power stroke. The airfoil kites are then reeled-in again along path 140d and the entire process repeats starting with power stroke 140a. Since the force to rewind the airfoils is much less than the force generated during reel-out, there is net power generated.

The invention discloses a rotating unit type double-frequency circular polarization reflective array antenna which comprises a circular polarization feed source and a reflective array. The circular polarization feed source comprises an axial mode spiral antenna. The reflective array is formed by a high band unit and a low band unit in an alternating-arraying mode. The high band unit and the low band unit carry out phase compensation in a rotating-band-unit mode, and accordingly the fact that after feed source irradiation, the reflective array can emit identical-phase circular polarization wave beams at the two bands can be guaranteed. A rotating technology is introduced to the units at the two bands on the same layer of array face, and cross coupling between the two bands is effectively lowered. The reflective array is of a single-layer structure, so that the array structure is simple and light.

External-cavity optically-pumped semiconductor lasers (OPS-lasers) including an OPS-structure having a mirror-structure surmounted by a surface-emitting, semiconductor multilayer (periodic) gain-structure are disclosed. The gain-structure is pumped by light from diode-lasers. The OPS-lasers can provide fundamental laser output-power of about two Watts (2.0 W) or greater. Intracavity frequency-converted arrangements of the OPS-lasers can provide harmonic laser output-power of about one-hundred milliwatts (100 mW) or greater, even at wavelengths in the ultraviolet region of the electromagnetic spectrum. These high output powers can be provided even in single axial-mode operation. Particular features of the OPS-lasers include a heat sink-assembly for cooling the OPS-structure, a folded resonator concept for providing optimum beam size at optically-nonlinear crystals used for frequency conversion, preferred selection of optically-nonlinear materials for frequency-conversion, and compound resonator designs for amplifying second harmonic-radiation for subsequent conversion to third or fourth harmonic radiation.

Provided are Circular Polarized Helical Radiation element and its Array Antenna operable in TX band and RX band. The circular polarized helical radiation element and its array antenna and the antenna with double reflection boards using that array can operate at TX / RX dual band which is high frequency such as Ka band by operating the helical antenna in axial mode and implementing dual feeding structure. The array antenna having a number of radiation elements operable in the both of TX band and RX band, wherein the radiation elements are arrayed on predetermined column lines, each radiation element comprising: a helix for radiating orthogonal circular polarized waves in the different frequency bands wherein the helix is fed at its beginning point and its terminating point; and a wave guide for accommodating the helix.

In an endoscope system including: a light emission unit emits laser light as illumination light or excitation light; a light guide unit guides the illumination light or the excitation light to an object; and an image pickup unit picks up a normal image formed with reflection light generated by reflection of the illumination light from the object or a fluorescence image emitted from the object in response to the excitation light. The laser light is multiaxial-mode laser light, or the light emission unit includes a plurality of laser-light sources which emit single-axial-mode laser beams having different wavelengths or phases. Alternatively, a vibration unit which vibrates the light guide unit is provided, or a high-frequency signal is superimposed on a driving current of the light emission unit, so that the wavelength of the laser light is shifted among a plurality of values.

Novel reconfigurable antennas are provided which may be used to accommodate the requirements for wideband multi-standard handheld communication devices. It is shown that using a shape memory alloy spring actuator, the height of a helical antenna and therefore the pitch spacing and angle can be varied. This can in turn tune the far-field radiation pattern and gain of the antenna dynamically to adjust to new operating conditions. The radiation pattern can further be directed using a two-helix array. Finally, a helical antenna embodiment is implemented and measured using a shape memory alloy actuator. Measurement results confirm that while keeping the centre frequency constant, gain tunability can be attained using this structure.

A CO2 laser reference oscillator (RO) can provide injection seeding to a Q-switched (QS) or Q-switched cavity dumped (QSCD) CO2 laser, where the output frequency of the RO laser is locked to the peak of the laser line by the use of appropriate electronics to dither one of the resonator mirrors of the reference oscillator. This injected radiation seeds the radiation building up within the Q-switched laser cavity, such that the oscillating frequency favors the wavelength of the injected radiation. An electronic feedback control circuit can be used to lock an axial mode of the Q-switched laser to line center. The change in build-up time of the pulses within the QS laser can be used to maintain cavity length at a value that enables oscillating at the peak of the same laser line that is injected into QS laser.

The invention discloses a planar two-arm axial-mode helix antenna suitable for a radio-frequency identification label. The planar two-arm axial-mode helix antenna comprises a dielectric plate, a planar two-arm axial-mode helical structure having an end-fire characteristic and an RFID label chip; a first microstrip line, a second microstrip line and a third microstrip line on the front side of the RFID label, and a fourth microstrip line and a fifth microstrip line on the back side of the RFID label form the planar two-arm axial-mode helical structure having the end-fire characteristic in a helical surrounding manner through three corresponding metalized through holes. The planar two-arm axial-mode helix antenna has a good end-fire characteristic, and can be matched with the RFID label chip easily, and is compact in structure and simple in production process, and the mutual coupling interference is small when multiple RFID labels are arranged.

A printed quasi-tapered tape helical element and printed helical array antenna. The helical element comprises a thin helix conductor having a uniform section associated with a tapered section. The helix conductor can be printed on a thin dielectric sheet and bonded to a hollow composite dielectric support. A solid copper conductor is configured to provide electrical connection between a feeding point of the helix conductor and a microstrip line of a microstrip feed network. The uniform and tapered helix turns are respectively wrapped around the uniform and tapered sections, which enables impedance matching, axial mode excitation, gain and radiation patterns, and damping out of standing waves generated in current distribution over the helix conductor. Conductive composite cups surrounding each helical element reduces mutual coupling in array environment. Thus, the helical element and the array antenna achieve low on-axis and off-axis axial ratio performance over the wideband for global coverage.

The invention relates to a measurement and test method for an axial torsional vibration mode of 300MW, 600MW, 1000MW turbine-generator set in a large-scale thermal power plant, and discloses a detecting method for an on-line dynamical frequency sweeping the axial torsional vibration mode by working a pumping signal on the excitation of power generator and combing the closed-circuit test which obtains the optimized response by a dynamically and continuously adjusting the pumping signal. The pumping signal with the mode characteristic is outputted through a method of dynamically on-line frequency sweeping. The excitation system of the turbine-generator set produces a controllable electric torque in the turbine-generator set through the excitation system so as to excite the axial torsional vibration of the turbine-generator set. Besides, the intensity of the axial vibration is measured to assure the fixed axial mode of the turbine-generator set. The method can measure the mechanical fixed frequency that is the axial torsional vibration mode of the turbine-generator set accurately, and is the basic research for solving the secondary in-phase vibration harm of the turbine-generator set. The invention is used for preventing, restraining and protecting the generator set and the power network from producing secondary in-phase vibration.