298results about "Electromagnetic transmission non-optical aspects" patented technology

A method and apparatus for establishing a terahertz link using a multi-element lens array that comprises a plurality of active beam steering device are disclosed. For example, the method receives detected terahertz signals from one or more detectors, where an active beam steering device is deployed with each of the one or more detectors, and determines, for each of the detected signals, if the detected signal is out of focus from a focus point. The method applies a corrective signal to each active beam steering device that corresponds to a detected terahertz signal that is out of focus from the focus point, wherein the corrective signal causes the detected signal to be redirected, and measures a signal-to-noise ratio of the detected signals. The method then establishes the terahertz link via at least one of the detected terahertz signals with a highest signal-to-noise ratio.

An analog signal receiver includes photonic sampling and electronic quantization. The receiver includes timing control circuitry configured to receive a series of optical pulses and output a plurality of timing signals based on the series of optical pulses to synchronize optical switches that receive a sampled optical signal to time deinterleave the optically sampled signal. The time deinterleaved signals are then sent to a plurality of demodulators wherein each demodulator receives at least one time deinterleaved optically sampled signal and at least one time deinterleaved optical reference signal to produce electrical signals based on the demodulated optical signals.

A wireless apparatus includes a millimeter-wave communication interface configured to exchange information within a millimeter-wave communication network, an UWB communication interface and control means or circuitry configured to activate the UWB interface for communicating location indication to the communication network according to an UWB communication standard. The location indication is intended for locating the wireless apparatus within the network.

A waveguide assembly for a use with, for example, a microwave receiver. The waveguide assembly includes: a waveguide; a tapered structure disposed within the waveguide, the tapered structure tapering in thickness from a first end with a zero height to a second end where the tapered structure has a height which nearly fills, but does not completely fill, the waveguide, to thereby define a modulator receiving space between the tapered structure and an adjacent wall of said waveguide. The second end of the tapered structure is preferably disposed adjacent an open circuited end of the waveguide. An electro-optic modulator is disposed on a dielectric substrate, the dielectric substrate being disposed at least partially within the modulator receiving space and the electro-optic modulator being disposed so that it is located, in use, at an antinode of a standing wave of the waveguide assembly.

The invention discloses a terahertz communication synchronization method, which belongs to the field of communication signal processing. According to the invention, a baseband signal inserted into a pilot frequency is upconverted to a terahertz band and transmitted to a wireless channel; after a wireless signal passes through a low noise amplifier, the first time of analog quadrature mixing is carried out to filter out high frequency components; after filtering is carried out again through a narrowband filter, downsampling, squared demodulating and fast Fourier transform are carried out in order; the maximum peak position is searched to find the corresponding frequency offset; the frequency offset is fed back to a local oscillator, so that the carrier frequency of a receiving end and the carrier frequency of a received signal are dynamically synchronized; the baseband signal with offset is acquired; the second time of analog quadrature mixing is carried out to filter out high frequencycomponents; sampling and fast Fourier transform are carried out; the signal peak is observed to acquire the estimated value of the frequency and the phase offset; and the frequency and phase of the sampling clock of a high-speed analog-to-digital converter are compensated to realize terahertz communication synchronization. According to the invention, the signal processing difficulty and hardwareoverhead can be reduced.

A physical area network described herein enables significantly improved health monitoring and treatment by utilizing internal (in-body) mechanisms and information and external mechanisms and information.

A method of and system of processing a phase-modulated optical signal includes performing, by demodulators, demodulation of the phase-modulated optical signal and outputting optical demodulated signals. The processing further includes performing, by pairs of gated photo detectors respectively connected to the I/Q demodulators, photo detection of the demodulated signals. The processing further tracks and holds electronicversions of the demodulated signals with a track and hold amplifier.

An optical wireless network includes an optical coupler for diverting received millimeter-wave signals comprised of an optical carrier and second order sidebands into multiple transmission paths; a downstream optical path being one of the multiple transmission paths and including an optical filter for filtering passing through the optical carrier with a single sideband, a converter for converting the optical carrier and single sideband to a corresponding electrical signal for amplification and broadcast transmission from an antenna; and an upstream path being one of the multiple transmission paths and having a filter for passing through the optical carrier only from the mm-wave signals and an intensity modulator driven by data received over the antenna to modulate the optical carrier for optical transmission to a receiving destination.

A microwave photonics based signal receiving device includes a signal generation module, a first Mach-Zehnder modulator, a dispersion module, a second Mach-Zehnder modulator, and a signal conversion module. The signal receiving device simplifies a structure of the signal receiving device by adopting quadrature demodulation. The signal receiving device demodulates a high-order modulation signal and flexibly adjusts a microwave carrier frequency.

A detection system includes a photonic module, a radio frequency (RF) module and processing circuitry. The photonic module may be configured to generate an optical tone for modulation in an optical domain prior to conversion to the RF domain. The RF module may be configured to interface with the photonic module to receive a transmission signal converted from the optical domain. The processing circuitry may be configured to interface with the photonic module and RF module to enable an operator to control of the photonic module and the RF module at least with respect to selectively determining a carrier frequency of the optical tone and a modulation technique to be employed with respect to the transmission signal converted from the optical domain.

Exemplary systems and methods can be provided for measuring a parameter—e.g., channel impulse response and/or power delay profile—of a wideband, millimeter-wave (mmW) channel. The exemplary systems can include a receiver configured to receive a first signal from the channel, generate a second signal, and measure the parameter based on a comparison between the first and second signals; and a controller configured to determine first and second calibration of the system before and after measuring the parameter, and determine a correction for the parameter measurement based on the first and second calibrations. Exemplary methods can also be provided for calibrating a system for measuring the channel parameter. Such methods can be utilized for systems in which the TX and RX devices share a common frequency source and for systems in which the TX and RX devices have individual frequency sources that free-run during channel measurements.

Provided is a broadband photomixer technology that is a core to generate continuous frequency variable and pulsed terahertz waves. It is possible to enhance light absorptance by applying the transmittance characteristic of a 2D light crystal structure and it is possible to increase the generation efficiency of terahertz waves accordingly. Moreover, it is possible to implement a wide area array type terahertz photomixer by applying an interdigit structure and spatially properly arranging a light crystal structure having various cycles. Accordingly, it is possible to solve difficulty in thermal characteristic and light alignment by mitigating the high light density of a light absorption unit and low photoelectric conversion efficiency is drastically improved. In addition, the radiation pattern of terahertz waves may be electrically controlled through the present invention.

A phased antenna array includes an array of antenna elements, and an electro-optic (EO) readout circuit coupled to the array of antenna elements. The EU readout circuit includes an optical source including a mode locked laser (MLL) configured to generate an optical carrier signal having beam carrier wavelengths, an EO modulator configured to modulate a signal from an antenna element based upon the optical carrier signal, a first WDM coupled downstream from the EO modulator, and optical-to-electrical converters coupled downstream from the first WDM. The first WDM is configured to multiplex each modulated beam carrier wavelength to a respective optical-to-electrical converter.

A method is provided of creating an end-to-end entanglement (89) between qubits in first and second end nodes (81L, 81R) of a chain of optically-coupled nodes whose intermediate nodes (80) are quantum repeaters. Local entanglements (85) are created between qubits in neighbouring pairs in the chain through interaction of the qubits with light fields transmitted between the nodes. A trigger (82) propagated along the chain from one end node (81L), sequentially enables each quantum repeater (100; 210) to effect a top-level cycle of operation. In each such cycle, a repeater (80) initiates a merging of two entanglements involving respective repeater qubits that are at least expected to be entangled with qubits in nodes disposed in opposite directions along the chain from the repeater. A quantum repeater (80) adapted for implementing this method is also provided.

The invention discloses a multi-dimensional multiplexing photon terahertz communication system, and the system comprises an optical frequency comb generation module, a wavelength division multiplexingmodule, a signal modulation module, an optical branching module, a space division multiplexing fan-in module, a multi-core optical fiber, a space division multiplexing fan-out module, a terahertz signal transmitting module, a terahertz prism and a terahertz signal receiving and demodulating module which are connected in sequence. According to the invention, the optical frequency comb generation module is adopted to generate optical frequency combs with wide bands and flat power distribution, and multiple paths of optical signals are simultaneously transmitted through the space division multiplexing fan-in fan-out module and the multi-core optical fiber. According to the photon terahertz wireless communication system, multiple multiplexing technologies are combined with the photon terahertz wireless communication system, the system can adjust the number of carriers through the wavelength division multiplexing module and adjust the number of branches through the space division multiplexing module, the data propagation rate of the Tbit/s magnitude can be achieved, the system capacity can be flexibly configured, the structure is simple, and the spectral efficiency is high.

Data is encrypted onto an electromagnetic beam by providing an electromagnetic beam having a signal component having a modal state, wherein the signal component is susceptible to accumulation of a geometric phase, and a reference component, transmitted along a path over at least part of which the signal component accumulates a geometric phase by transformation of its modal state from a first to a second modal state, from the second to at least one further modal state, and then back to the first modal state; and modulating with the data the geometric phase so accumulated, by modulating the modal state transformations. Data is decrypted from a received electromagnetic beam by corresponding processing of the received electromagnetic beam and by comparing an overall phase of the signal component with an overall phase of the reference component so as to retrieve the modulation.

Apparatus for transmitting and receiving information using one or more quantum-entangled particles. The apparatus may include a first substrate including a first row of quantum dots and a second substrate including a second row of quantum dots. The apparatus may also include a beam splitter configured to inject a first particle into a first quantum dot and to inject a second particle into a second quantum dot. A physical property of the first particle may be in a quantum-entangled state with a physical property of the second particle. The apparatus may further include a first wave source configured to move the first particle along the first row of quantum dot, and a second wave source configured to move the second particle along the second row of quantum dots.

A Periodic Cluster State Generator (PCSG) consisting of a monolithic integrated waveguide device that employs four wave mixing, an array of probabilistic Photon Guns, single mode Sequential Entanglers and an array of controllable entangling gates between modes to create arbitrary size and shape cluster states with several constraints. The cluster state is assumed linear or square lattice. Only nearest neighbor qubits are entangled. Such a cluster state resource has been proven to be able to perform universal quantum computing if the initial state is large enough.

The disclosure relates to a grid-controlled X-ray source, a space X-ray communication system and a space X-ray communication method. The structure of the grid-controlled X-ray source is: one end of the filament is grounded and the other end is connected with the anode of a power supply, the thermionic cathode is located at the side of the filament and the emergence hole thereof faces the filament, the modulation grid is an electrode plate with a small hole which faces the emergence hole of the thermionic cathode, the electronic beam focusing electrode is located on the two sides of the small hole of the modulation grid to form a focusing channel facing the small hole, an electronic beam is focused by the electronic beam focusing electrode and then transmitted to the metallic target anode, wherein the transmitting surface of the metallic target anode faces the outlet of the focusing channel and the other surface is connected with the anode of the power supply, and the output window is located on an reflection path of the electronic beam which is from the metallic target anode. The disclosure solves the technical problems that the signal-to-noise ratio of communication is low, the error rate error rate of communication is high and the speed of communication is low when an X ray is used for implementing communication in the conventional art, and has the advantages of long communication distance and the low error rate of communication.

The embodiment of the invention discloses a method and a device for generating frequency doubling millimeter wave. The method comprises the following steps that: an intensity modulator modulates a radio frequency signal onto an optical wave, outputs an optical carrier and two n-order optical sidebands and separates the optical carrier and the two n-order optical sidebands; a baseband signal is loaded onto the optical carrier via the intensity modulator; the two n-order optical sidebands are locked by a laser; the optical carrier loaded with baseband data and the two locked n-order optical sidebands are subject to four-wave mixing to generate an optical millimeter wave signal with 4n-time frequency of the radio frequency signal; and the optical millimeter wave signal is subject to beat frequency to generate an electric millimeter wave signal. The device comprises: a modulation module, a mode locking module, a four-wave mixing module and a beat frequency module. The invention provides a method and a device for generating frequency doubling millimeter wave, which can generate millimeter wave signals with high frequency and quality by utilizing low radio frequency source.