33results about How to "Flexible tuning" patented technology

The invention discloses a reconfigurable single-band-pass microwave photon filtering system and method and belongs to the technical field of microwave photons. A device comprises a laser, an optical divider, an electro-optic phase modulator, an optical isolator, a first polarization controller, a high-nonlinearity medium, a pumping microwave source, an electro-optic intensity modulator, an optical amplifier, a second polarization controller, an optical circulator and a photoelectric detector. According to the microwave photon filtering system, single-band-pass photon filtering is conducted by utilizing a stimulated brillouin scattering effect in the high-nonlinearity medium, and a function of filtering reconfiguration is achieved by controlling the frequency spectrum of pumping microwave. The system and method solves the problem that the existing periodical microwave photon filtering system is limited in filtering range and the filtering waveform is not easy to reconfigure, and has the advantages of being high in stability and convenient to operate.

The invention relates to the technical field of communication, and particularly relates to an antenna and a mobile terminal. The antenna comprises a system ground, a closed metal ring and a main board electrically connected with the system ground; the metal ring is electrically connected with the system ground; a radiation body is formed on the part, from a first position to a second position, on the metal ring; the main board is provided with a grounding circuit, a first tuning switch, a second tuning switch, a feeder circuit and an impedance matching circuit; the grounding circuit is electrically connected with a first grounding point, and electrically connected with the metal ring in the third position of the metal ring; the first tuning switch is electrically connected between the first grounding point and the grounding circuit; the second tuning switch is electrically connected between a second grounding point and the fourth position of the metal ring; the feeder circuit is electrically connected with a feeding point, and electrically connected with the metal ring in the fifth position of the metal ring; and the impedance matching circuit is electrically connected between the feeding point and the feeder circuit.

The invention discloses a broadband continuous tuning optical carrier microwave filtering device, which comprises spectral hole-burning crystal, a low-temperature thermostat, an electrooptical modulator, a carrier wave laser, an optical fiber collimator, a frequency accurate-tuning laser, an arbitrary signal generator, a converging lens and an extender lens, wherein the frequency accurate-tuning laser emits a hole-burning preset laser light to irradiate the crystal; ions with a corresponding frequency are excited to an upper energy level; within the lifetime of the upper energy level, a spectral burnt hole with a corresponding laser light frequency is left in the crystal; a microwave signal is loaded to a carrier wave laser light through the electrooptical modulator; and when to-be-filtered optical carrier microwave signals irradiate the same position of the crystal, the optical carrier microwave signal with the corresponding spectral hole-burning frequency passes through the crystal and the signals with other frequencies are absorbed by the crystal, so that reconfigurable and tunable optical carrier microwave signal filtering is achieved. The broadband continuous tuning optical carrier microwave filtering device has the characteristics of being flexible, tunable, reconfigurable and the like within a broad frequency range on the basis of transient spectral hole burning; and the single-passband frequency response is easy to achieve.

The invention provides a graphene and nano antenna array-based tunable directional coupler, which comprises a nano antenna array, a first graphene layer and a waveguide, wherein the nano antenna arrayis arranged on the upper surface of the first graphene layer; the first graphene layer is arranged above the waveguide; the nano antenna array is used for highly and directionally coupling an opticalsignal component meeting a preset polarization direction in free space and in a tunable directional coupler working band to a specific mode in the waveguide; and the first graphene layer is used forchanging the working wavelength of the tunable directional coupler under effects of external voltage. According to the graphene and nano antenna array-based tunable directional coupler provided in theinvention, as the first graphene layer is used for changing the working wavelength of the tunable directional coupler under effects of external voltage, high-speed and real-time tuning on the workingwavelength of the tunable directional coupler can be realized.