Showing papers on "Radio frequency published in 2006"
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24 Jul 2006TL;DR: In this paper, a system and device for harvesting various frequencies and polarizations of ambient radio frequency (RF) electromagnetic (EM) energy for making a passive sensor (tag) into an autonomous passive sensor adapted to collect and store data with time-stamping and some primitive computation when necessary even when an interrogating radio frequency identification (RFID) reader is not present (not transmitting).
Abstract: A system and device for harvesting various frequencies and polarizations of ambient radio frequency (RF) electromagnetic (EM) energy for making a passive sensor (tag) into an autonomous passive sensor (tag) adapted to collect and store data with time-stamping and some primitive computation when necessary even when an interrogating radio frequency identification (RFID) reader is not present (not transmitting). A specific source of ambient RF EM energy may include wireless fidelity (WiFi) and/or cellular telephone base stations. The system and device may also allow for the recharging of energy storage units in active and battery assisted passive (BAP) devices. The system could be a “smart building” that uses passive sensors with RF EM energy harvesting capability to sense environmental variables, security breaches, as well as information from “smart appliances” that can be used for a variety of controls and can be accessed locally or remotely over the Internet or cellular networks.
430 citations
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05 Jul 2006TL;DR: It is demonstrated theoretically and by means of an experimental system that the high peak-to-average ratio in OFDM can be exploited constructively in visible light communication to intensity modulate LEDs.
Abstract: In this paper wireless communication using white, high brightness LEDs (light emitting diodes) is considered. In particular, the use of OFDM (orthogonal frequency division multiplexing) for intensity modulation is investigated. The high peak-to-average ratio (PAR) in OFDM is usually considered a disadvantage in radio frequency transmission systems due to non-linearities of the power amplifier. It is demonstrated theoretically and by means of an experimental system that the high PAR in OFDM can be exploited constructively in visible light communication to intensity modulate LEDs. It is shown that the theoretical and the experimental results match very closely, and that it is possible to cover a distance of up to one meter using a single LED.
353 citations
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19 Apr 2006
TL;DR: In this article, a system and method for powering a vehicle using radio frequency (RF) signals is described, which includes positioning a plurality of RF generators beneath the road surface of a roadway, the RF generators configured to transmit RF signals in the direction of vehicles traveling over the roadway, coupling a rectenna on a vehicle and using the power generated by the rectenna to power the vehicle.
Abstract: A system and method are described for powering a vehicle using radio frequency (“RF”) signals. For example, a method according to one embodiment of the invention comprises: positioning a plurality of RF generators beneath the road surface of a roadway, the RF generators configured to transmit RF signals in the direction of vehicles traveling over the roadway; coupling a rectenna on a vehicle, the rectenna configured to receive the RF signals transmitted from the RF generators and to generate power from the RF signals; and using the power generated by the rectenna to power the vehicle.
253 citations
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19 Jan 2006TL;DR: In this paper, an apparatus and method for using ambient RF power in a portable terminal is described. But the authors focus on the charging apparatus and do not consider the use of RF signals.
Abstract: An apparatus and method for using ambient RF power in a portable terminal are provided. In the charging apparatus, an antenna array receives RF signals left derelict in the air, a rectifier rectifies the RF signals to DC voltages, and a power storage stores the DC voltages as power.
220 citations
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TL;DR: This paper presents two new useful forms of the radio link budget that describe the power link of an RF tag system when the tag is attached to an object and quantifies the reduction in RF tag antenna gain due to material attachment.
Abstract: Passive radio frequency (RF) tags in the UHF and microwave bands have drawn considerable attention because of their great potential for use in many radio frequency identification (RFID) applications. However, more basic research is needed to increase the range and reliability of a passive RF tag's radio link, particularly when the RF tag is placed onto any lossy dielectric or metallic surface. This paper presents two new useful forms of the radio link budget that describe the power link of an RF tag system when the tag is attached to an object. These radio link budgets are dependent upon the gain penalty, a term which quantifies the reduction in RF tag antenna gain due to material attachment. A series of measurements, or radio assay, was used to measure the far-field gain pattern and gain penalty of several flexible 915 MHz antennas when attached to cardboard, pine plywood, acrylic, deionized water, ethylene glycol, ground beef, and an aluminum slab. It is shown that the gain penalty due to material attachment can result in more than 20 dB of excess loss in the backscatter communication link.
214 citations
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TL;DR: In this paper, the authors show that organic transistor based full-wave rectifier circuits utilizing pentacene, a p-channel organic semiconductor, can operate at this frequency with a useful efficiency.
Abstract: One important technical hurdle that has to be overcome for using organic transistors in radio-frequency identification tags is for these devices to operate at rf frequencies (typically 13.56MHz) in the front end. It was long thought that organic transistors are too slow for this. In this letter we show that organic transistor based full-wave rectifier circuits utilizing pentacene, a p-channel organic semiconductor, can operate at this frequency with a useful efficiency. In order to achieve such high-frequency operation, we make use of the nonquasistatic state of the transistors.
207 citations
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23 Apr 2006
TL;DR: NCCR-MICS/CL3 Reference LCA-CONF-2005-029 Record created on 2005-12-07, modified on 2017-05-12.
Abstract: Keywords: NCCR-MICS ; NCCR-MICS/CL3 Reference LCA-CONF-2005-029 Record created on 2005-12-07, modified on 2017-05-12
200 citations
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TL;DR: In this paper, a differential tunable active inductor for the LC-tank was used for a wide tuning-range CMOS voltage-controlled oscillator (VCO) with an output frequency from 500 MHz to 3.0 GHz.
Abstract: By utilizing a differential tunable active inductor for the LC-tank, a wide tuning-range CMOS voltage-controlled oscillator (VCO) is presented. In the proposed circuit topology, the coarse frequency tuning is achieved by the tunable active inductor, while the fine tuning is controlled by the varactor. Using a 0.18-mum CMOS process, a prototype VCO is implemented for demonstration. The fabricated circuit provides an output frequency from 500 MHz to 3.0 GHz, resulting in a tuning range of 143% at radio frequencies. The measured phase noise is from -101 to -118 dBc/Hz at a 1-MHz offset within the entire frequency range. Due to the absence of the spiral inductors, the fully integrated VCO occupies an active area of 150times300 mum2
169 citations
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TL;DR: In this article, a series resonance between the capacitive sheath and the inductive and ohmic bulk of the plasma was investigated, and a simple analytical investigation was introduced to solve the nonlinear equations analytically, a series of approximation is necessary.
Abstract: Self-excited plasma series resonances (PSR) are observed in capacitve discharges as high-frequency oscillations superimposed on the normal rf current. This high-frequency contribution to the current is generated by a series resonance between the capacitive sheath and the inductive and ohmic bulk of the plasma. The nonlinearity of the sheath leads to a complex dynamic. The effect is applied, e.g., as a diagnostic technique in commercial etch reactors where analysis is performed by a numerical model. Here a simple analytical investigation is introduced. In order to solve the nonlinear equations analytically, a series of approximation is necessary. Nevertheless, the basic physics is conserved and excellent agreement with numerical solutions is found. The model provides explicit and simple formula for the current waveform and the spectral range of the oscillations. In particular, the dependence on the discharge parameters is shown. Further, the model gives insight into an additional dissipation channel opened by the high-frequency oscillations. With decreasing pressure, the ohmic resistance of the bulk decreases as well, while the amplitude of the PSR oscillations grows. This results in substantially higher power dissipation that exceeds the contribution of classical stochastic heating.
163 citations
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TL;DR: An industrial, confined, dual frequency, capacitively coupled, radio-frequency plasma etch reactor (Exelan®, Lam Research) has been modified for spatially resolved optical measurements.
Abstract: An industrial, confined, dual frequency, capacitively coupled, radio-frequency plasma etch reactor (Exelan®, Lam Research) has been modified for spatially resolved optical measurements. Space and phase resolved optical emission spectroscopy yields insight into the dynamics of the discharge. A strong coupling of the two frequencies is observed in the emission profiles. Consequently, the ionization dynamics, probed through excitation, is determined by both frequencies. The control of plasma density by the high frequency is, therefore, also influenced by the low frequency. Hence, separate control of plasma density and ion energy is rather complex.
162 citations
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TL;DR: In this paper, an optical interleaver was employed to separate the spectrum of the double-sideband signals generated by a single-arm intensity external modulator, and the separated first-order sideband modes were used to generate optical millimeter-wave with double RF frequency, while the separated optical carrier was reused for uplink connection.
Abstract: We proposed and experimentally demonstrated a novel scheme to generate an optical millimeter-wave and realized wavelength reuse for uplink connection in a radio-over-fiber system. We employed an optical interleaver to separate the spectrum of the double-sideband signals generated by a single-arm intensity external modulator. The separated first-order sideband modes were used to generate optical millimeter-wave with double RF frequency, while the separated optical carrier was reused for uplink connection
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30 Jun 2006TL;DR: In this paper, a simple system for measuring the peer-to-peer radio frequency time of flight between two identical sensor motes for distance measurement is presented, using a 2.4 GHz radio, simple real time processing, and offline range extraction.
Abstract: A simple system for measuring the peer to peer radio frequency time of flight between two identical sensor motes for distance measurement is presented. This scheme uses a 2.4 GHz radio, simple real time processing, and offline range extraction. Methods for reducing error from clock offset and multipath propagation are presented and implemented on prototype hardware. Measurement results are presented including measurements taken in a coal mine. Typical ranging accuracies are between 1 mRMS and 3 mRMS.
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08 Sep 2006TL;DR: In this article, Taps are affixed to the outer conductor of a coaxial transmission line and include field coupling portions extending into the internal field region of the coaxial line.
Abstract: A system and method for signal distribution within a sensor array uses a coaxial transmission line. Taps are affixed to the outer conductor of the coaxial transmission line and include field coupling portions extending into the internal field region of the coaxial transmission line. Electromagnetic energy propagating within the transmission line can be extracted to power the sensors. Sensor signals can be modulated onto radio frequency signals and propagated along the transmission line to distribute the sensor signals.
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29 Dec 2006
TL;DR: In this paper, a reaction chamber is used to contain an etching gas, and an RF power source is adapted to output RF power for excitation of the gas to generate plasma.
Abstract: A plasma etching method includes preparing in a reaction chamber a semiconductor substrate on which a material layer to be etched is provided; and injecting an etching gas into the reaction chamber, the etching gas being ionized through an RF (Radio Frequency) power source to generate a plasma, wherein the RF power source outputs RF power in a pulse output mode. The plasma etching apparatus includes a reaction chamber adapted to contain an etching gas; and an RF power source adapted to output RF power for excitation of the etching gas to generate plasma, wherein the apparatus further include a pulse control circuit adapted to control the RF power source to output RF power in a pulse output mode. With the invention, the plasma for etching can be generated in a pulse output mode, thus improving a precision of an endpoint where the etching can be disabled.
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13 Jun 2006TL;DR: Dynamic performance of high-speed high-resolution digital-to-analog converters (DACs) is limited by distortion at the data switching instants, so a DAC output controlled by an oscillating waveform is proposed to mitigate the effects of switching distortion and clock jitter.
Abstract: A radio frequency digital-to-analog converter with a programmable current output. In exemplary aspects of the invention, improved apparatus and methods for providing (i) current mirror matching, (ii) enhanced current pulse rising edge performance, (ii) reduced base voltage swing, and (iv) compensated high voltage swing, are provided. The foregoing apparatus and methods can be applied to any RF signal application (wireless or otherwise), including for example wireless cellular handsets.
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24 Apr 2006TL;DR: A new architecture for wireless power and data telemetry that recovers power and a system clock from a weak incident RF signal, incorporating an on-chip ADC, and employing active telemetry for data transmission is presented.
Abstract: We present a new architecture for wireless power and data telemetry that recovers power and a system clock from a weak incident RF signal. A high-efficiency RF-DC converter generates a 3-VDC supply for the system from a -12.3-dBm incident RF signal, gathered by a commercial 50-/spl Omega/ antenna. A system clock is extracted from the same incident signal, by an injection-locked LC oscillator. Sub-harmonic injection-locking facilitates the separation of the incident and the transmit signal frequencies, without need for a PLL. The proposed architecture is used in a long-range telemetry device, incorporating an on-chip ADC, and employing active telemetry for data transmission. Data is transmitted through binary phase-shift-keying of a 900-MHz carrier. The prototype, implemented in 0.25-/spl mu/m CMOS, occupies less than 1 mm/sup 2/. A wireless operation range of more than 18 meters is indicated by anechoic chamber testing.
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10 Apr 2006TL;DR: In this paper, a completely passive radio frequency tag is proposed, utilizing the scattering from electrically small but resonant inclusions, which can be used in some applications of radio frequency identification systems.
Abstract: A completely passive radio frequency tag is proposed, utilizing the scattering from electrically small but resonant inclusions. When placing these space-filling curve inclusions in an array and scaling each element within the array such that each element has its own separate resonant frequency, a radio frequency barcode can be developed from the radar cross section of the array. The narrow bandwidth inherent to such inclusions can be helpful in packing the overall signature into a relatively small frequency spectrum. Such radio frequency tags may have potential use in some applications of radio frequency identification systems.
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TL;DR: A scaled down version of a toroidal radio frequency (RF) ion trap mass analyzer operating with RF trapping voltages on the order of 1 kVp-p was proposed in this article.
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TL;DR: It is shown that the narrow electrode gap deforms the discharge structure, ultimately removing the bulk-plasma region and disabling electron trapping, allowing rf atmospheric microplasmas to operate at very high current densities thus simultaneously achieving higher stability and greater chemical reactivity.
Abstract: Conventional radio-frequency (rf) nonthermal atmospheric plasmas are generated in a millimeter gap. In this Letter, we present a self-consistent numerical study of rf atmospheric microplasmas in a submillimeter gap comparable to their sheath thickness. It is shown that the narrow electrode gap deforms the discharge structure, ultimately removing the bulk-plasma region and disabling electron trapping. Significantly, these properties permit rf atmospheric microplasmas to operate at very high current densities thus simultaneously achieving higher stability and greater chemical reactivity.
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27 Sep 2006
TL;DR: In this article, a medical device adapted for implantation into a patient receives electrical power from an extravascular power supply, which includes a source of electrical power and a power transmitter that emits the first RF signal which is varied in response to the indication from the second radio frequency signal.
Abstract: A medical device adapted for implantation into a patient receives electrical power from an extravascular power supply. The medical device has a first receiver for a first radio frequency (RF) signal from which energy is extracted to power the medical device, and a second RF signal carries an indication of an amount of that extracted energy. The extravascular power supply includes a source of electrical power and a power transmitter that emits the first RF signal which is varied in response to the indication from the second radio frequency signal. Animal physiological data also can be carried by the second RF signal. The medical device includes a system that monitors the effects of tissue stimulation and regulates subsequent stimulation accordingly.
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TL;DR: This error suppression was investigated through simulation experiments and in vivo experiments on the human carotid artery using a correlation estimator with quadrature demodulated complex signals.
Abstract: Noninvasive measurement of mechanical properties, such as elasticity, of the arterial wall, is useful for diagnosis of atherosclerosis. The elasticity of the arterial wall can be estimated by combining measurement of displacement of the arterial wall with that of blood pressure. In general, the displacement of the arterial wall is estimated from the phase shift of radio frequency (RF) echoes between two consecutive frames using a correlation estimator with quadrature demodulated complex signals. Recently, digitized data of broadband RF echoes are available in modern diagnostic equipment. The Fourier transform can be used to estimate the phase of the RF echo at each frequency within the RF frequency bandwidth. Therefore, the phase shifts between RF echoes of two consecutive frames can be estimated at multiple frequencies. In this estimation, due to object displacement, the RF echo is time shifted in comparison with that of the previous frame. However, the position of the time window for the Fourier transform is not changed between two consecutive frames. This change in relative position between the RF echo and the time window has a strong influence on the estimation of the artery-wall displacement, resulting in error. To suppress this error, the phase shift should be estimated at the actual RF center frequency. In this paper, this error suppression was investigated through simulation experiments and in vivo experiments on the human carotid artery.
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02 Jun 2006TL;DR: In this paper, a system and method for detecting use of RF transmit devices (e.g., cellular phones) in a vehicle is presented, which includes a first RF antenna for detecting signal strength of an RF signals transmit device at a first location in the vehicle and a power first detector for generating a first output signal indicative thereof.
Abstract: A system and method are provided for detecting use of RF transmit devices (e.g., cellular phones) in a vehicle. The system includes a first RF antenna for detecting signal strength of an RF signals transmit device at a first location in a vehicle and a power first detector for generating a first output signal indicative thereof. The system also includes a second antenna for detecting signal strength of the RF signals at a second location in the vehicle and a second power detector for generating a second output signal indicative thereof. The system further includes a signal processor for processing the first and second output signals to determine the presence of an RF transmit device in use in the vehicle and to further determine the location of the RF transmit device to determine if a driver is using the device.
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01 Jan 2006TL;DR: A prototype of dual band telemetry for a retinal prosthetic device has been built and experimental results show that both power and data can be transmitted and high data rate can be achieved without compromising the power transmission efficiency.
Abstract: Inductive coupling is commonly used for wireless power and data transfer in biomedical telemetry systems. The increasing demand on the performance of medical devices requires high data rate and high power efficiency at the same time. If only one radio frequency carrier is used, it is difficult to achieve both high data rate and high power efficiency due to the competing requirements on carrier frequency and system-Q of the power and data transmission. We propose a dual band telemetry system to implement power and data transmission using different frequencies by allocating lower frequency for power transmission and higher frequency for data transmission. However, the magnetic coupling between the power carrier and data carrier will affect the operation of both links. In this paper, this interference is analyzed and design equations are derived, which are used to design coils to maximize the data signal level received at the implant side. A prototype of dual band telemetry for a retinal prosthetic device has been built and experimental results show that both power and data can be transmitted and high data rate can be achieved without compromising the power transmission efficiency.
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TL;DR: In this article, the authors proposed a method to find the ranges of valid bandpass sampling frequency for direct downconverting multiband RF signals, which can be used to design a multiband receiver for software defined radios.
Abstract: -Bandpass sampling can be used by radio receivers to directly digitize the radio frequency (RF) signals. Although the bandpass sampling theory for single-band RF signals is well established, its counterpart for multiband RF signals is relatively immature. In this paper, we propose a novel and efficient method to find the ranges of valid bandpass sampling frequency for direct downconverting multiband RF signals. Simple formulas for the ranges of valid bandpass sampling frequency in terms of the frequency locations of the multiple RF bands are derived. The result can be used to design a multiband receiver for software defined radios.
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TL;DR: Results show that higher-quality images can be reconstructed with the square-wave aperture Weighting method due to an increased penetration depth as compared to the exact weighting method developed previously, and a frame rate of 486 per second was achieved at a pulse repetition frequency of about 5348 Hz for the human heart.
Abstract: A general-purpose high frame rate (HFR) medical imaging system has been developed. This system has 128 independent linear transmitters, each of which is capable of producing an arbitrary broadband (about 0.05-10 MHz) waveform of up to plusmn144 V peak voltage on a 75-ohm resistive load using a 12-bit/40-MHz digital-to-analog converter. The system also has 128 independent, broadband (about 0.25-10 MHz), and time-variable-gain receiver channels, each of which has a 12-bit/40-MHz analog-to-digital converter and up to 512 MB of memory. The system is controlled by a personal computer (PC), and radio frequency echo data of each channel are transferred to the same PC via a standard USB 2.0 port for image reconstructions. Using the HFR imaging system, we have developed a new limited-diffraction array beam imaging method with square-wave aperture voltage weightings. With this method, in principle, only one or two transmitters are required to excite a fully populated two-dimensional (2-D) array transducer to achieve an equivalent dynamic focusing in both transmission and reception to reconstruct a high-quality three-dimensional image without the need of the time delays of traditional beam focusing arid steering, potentially simplifying the transmitter subsystem of an imager. To validate the method, for simplicity, 2-D imaging experiments were performed using the system. In the in vitro experiment, a custom-made, 128-element, 0.32-mm pitch, 3.5-MHz center frequency linear array transducer with about 50% fractional bandwidth was used to reconstruct images of an ATS 539 tissue-mimicking phantom at an axial distance of 130 mm with a field of view of more than 90deg. In the in vivo experiment of a human heart, images with a field of view of more than 90deg at 120-mm axial distance were obtained with a 128-element, 2.5-MHz center frequency, 0.15-mm pitch Acusori V2 phased array. To ensure that the system was operated under the limits set by the U.S. Food and Drug Administration, the mechanical index, thermal index, and acoustic output were measured. Results show that higher-quality images can be reconstructed with the square-wave aperture weighting method due to an increased penetration depth as compared to the exact weighting method developed previously, and a frame rate of 486 per second was achieved at a pulse repetition frequency of about 5348 Hz for the human heart
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17 Nov 2006TL;DR: In this paper, an optical branching portion branches the intensity-modulated optical signal and respectively outputs branched optical signals to radio base stations to obtain an RF signal by frequency-converting the IF signal.
Abstract: Modulators respectively modulate baseband signals into IF signals having different frequencies. A multiplexer multiplexes the IF signals. An electrical-optical converter intensity modulates the multiplexed IF signals into optical signals. A local oscillation signal source outputs a predetermined local oscillation signal. An external modulator intensity-modulates the optical signal using the local oscillation signal. An optical branching portion branches the intensity-modulated optical signal and respectively outputs branched optical signals to radio base stations. An optical-electrical converter converts the optical signal into an electric signal, to obtain an RF signal by frequency-converting the IF signal. An antenna only transmits a component having a desired radio frequency extracted in a band filter from the RF signal to a subscriber terminal. Frequency conversion from the IF signal to the RF signal is thus optically performed, whereby the frequency or electrical-optical converter is shared among the radio base stations.
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TL;DR: A broadband microwave/millimeter-wave (MMW) Gilbert-cell mixer using standard 1P8M 0.13/spl mu/m complementary metal oxide semiconductor (CMOS) technology is presented in this paper.
Abstract: A broadband microwave/millimeter-wave (MMW) Gilbert-cellmixer using standard 1P8M 0.13-/spl mu/m complementary metal oxide semiconductor (CMOS) technology is presented in this letter. Two radio frequency (RF) transformer baluns are used in RF-and local oscillator (LO)-ports to convert single-ended signals to differential signals. Thin film microstrip line is employed for the matching networks and transformer design. This mixer has a conversion gain of better than 5dB from 9 to 50GHz. Between 5 and 50GHz,the RF- and LO-to-intermediate frequency (IF) isolations are better than 40dB. The RF-to-LO and LO-to-RF isolations are all better than 20dB. To the authors' knowledge, this is the first CMOS Gilbert-cell mixer operating to MMW frequency to date.
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03 Aug 2006
TL;DR: In this paper, a method for imaging includes directing a plurality of radio frequency (RF) beams toward a target organ from a plurality-of-angles (VOA) angle, and local tissue parameters at multiple points in the target organ are extracted by jointly processing the RF signals in each of the second pairs.
Abstract: A method for imaging includes directing a plurality of radio frequency (RF) beams toward a target organ from a plurality of angles. The RF beams include one or more first pairs of the RF beams, each first pair including two of the RF beams that impinge on the target organ from opposite directions. RF signals reflected from the target organ are received responsively to the RF beams, the RF signals including one or more second pairs of the RF signals engendered respectively by the one or more first pairs of the RF beams. Local tissue parameters at multiple points in the target organ are extracted by jointly processing the RF signals in each of the second pairs. Images of the target organ are produced using the extracted local tissue parameters. Other embodiments described herein include methods for passive imaging, motion vector analysis, ablation, local heating and application of electromagnetic pressure.
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29 Aug 2006
TL;DR: In this paper, a method and apparatus for thermal treatment of tissue by irradiating the skin with electromagnetic energy is disclosed, which includes either a positional sensor or a dosage evaluation sensor, or both types of sensors provide feedback to a controller.
Abstract: A method and apparatus for thermal treatment of tissue by irradiating the skin with electromagnetic energy is disclosed. Sources of electromagnetic energy include radio frequency (RF) generators, lasers, and flashlamps. The apparatus includes either a positional sensor or a dosage evaluation sensor, or both types of sensors. These sensors provide feedback to a controller. The controller may control the electromagnetic source parameters, the electromagnetic source activation, and/or the sensor measurement parameters. An additional scanning delivery unit may be operably coupled to the controller or to the sensors to provide a controlled distribution of electromagnetic energy to the target region of the skin. The use of positional measurement sensors and dosage evaluation sensors permits the controller to automatically determine the proper electromagnetic source parameters including, for example, pulse timing and pulse frequency.
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TL;DR: In this article, an electromagnetic cavity resonator based sensor for multiphase flow measurement through an oil pipeline was developed, in conjunction with Solartron ISA, in order to detect pipeline contents using resonant peaks captured instantaneously.
Abstract: We have developed, in conjunction with Solartron ISA, an electromagnetic cavity resonator based sensor for multiphase flow measurement through an oil pipeline. This sensor is non-intrusive and transmits low power (10 mW) radio frequencies (RF) in the range of 100–350 MHz and detects the pipeline contents using resonant peaks captured instantaneously. The multiple resonances from each captured RF spectrum are analysed to determine the phase fractions in the pipeline. An industrial version of the sensor for a 102 mm (4 inch) diameter pipe has been constructed and results from this sensor are compared to those given by simulations performed using the electromagnetic high frequency structure simulator software package HFSS.