1301 results about "Diplexer" patented technology

A device and method for providing power line communications via an underground residential distribution power system is provided. One embodiment of the present invention includes a medium voltage interface device that may include a first port configured to communicate over the power line and a network interface. A first amplifier may form part of a first communication path between the first port and the network interface and be configured to amplify data signals transmitted via the first port. In addition, a second amplifier may form part of a second communication path between the first port and the network interface and be configured to amplify data signals received via the first port. In addition, the embodiment may include a diplexer forming part of the first communication path between the first amplifier and the first port and forming part of the second communication path between the second amplifier and the first port. The device may include an electro-optic converter coupled to the network interface to convert between electrical and optic data signals, wherein the network interface is configured to communicate via one or more fiber optic conductors.

A multi-band antenna switch circuit including a diplexer connected to an antenna terminal for demultiplexing signals of different passing bands, a first and a second switch circuit for switching a high frequency signal and a low frequency signal demultiplexed by the diplexer to a plurality of transmission / reception terminals, a first and a second low pass filter connected to a transmission path between the diplexer and the transmission terminal or between the first and the second switch circuit and the transmission terminal, and a notch filter provided between the diplexer and the first switch circuit or between the diplexer and the second switch circuit. The multi-band antenna switch circuit includes a high pass filter having an input terminal and an output terminal and provided at least between die diplexer and the antenna terminal and including a first inductor connected between the input terminal and the ground, a first capacitor connected between the input terminal and the output terminal, a second inductor connected to the output terminal, and a second capacitor connected between the second inductor and the ground.

Apparatus for detecting vulnerable plaques embedded in the wall of a patient's blood vessel includes an intravascular catheter containing a microwave antenna, an extra-corporeal radiometer having a signal input, a reference input and an output, a cable for electrically connecting the antenna to the signal input, and a device for applying an indication of the patient's normal tissue temperature to the reference input so that when the catheter is moved along the vessel, the locations of the vulnerable plaques are reflected in a signal from the output as thermal anomalies due to the higher emissivity of the vulnerable plaques as compared to the normal tissue. A second embodiment of the apparatus has two coaxial antennas in the catheter serving two radiometers. One measures the temperature at locations in the vessel wall, the other measures the temperature at the surface. By subtracting the two signals, the locations of vulnerable plaque may be visualized. The apparatus employs a special diplexer for separating the signals from the two antennas and a method of detecting and possibly destroying the plaques is also disclosed.

An apparatus and method for enabling cost-effective duplex communication by diplexing one of down stream signals for frequency up-conversion in a hybrid fiber-radio system includes diplexing an unmodulated mode signal among beating signals between a master laser and an injection-locked slave laser and using the diplexed signal for down-conversion in upstream transmission, thereby eliminating the need for expensive high-frequency local oscillators for frequency conversion. Higher radio frequency signals can be generated using beating between basic modes and satellite modes such as FWM conjugates of the master laser and slave laser. Cost-effective systems, stabilization of a light source and improved transmission performance may be achieved by using a diplexer instead of an expensive high-frequency local oscillator.

Medical catheter apparatus for minimally invasive applications includes a probe for radiating electromagnetic waves of a first frequency capable of heating tissue and detecting thermal emissions from that tissue of a second frequency indicative of tissue temperature. The probe has an inner conductor extending along the probe to a conductive probe tip and a concentric tubular outer conductor having a leading end spaced rearwardly from the probe tip and a closed trailing end shorted to the inner conductor. A dielectric sheath surrounds the outer conductor which sheath has a leading end spaced rearwardly from the leading end of the outer conductor. A diplexer integrated into the probe includes a filter circuit positioned inside the outer conductor and a coupling capacitor connected between a point on the inner conductor and the input of the filter circuit such that the conductors between that point and the shorted trailing end of the outer conductor constitute a quarter wave stub at the second frequency.

An optical sensing system uses light scattered from a sensing fibre to sense conditions along the fibre, and has a receiver with a frequency to amplitude converter to obtain a frequency of a Brillouin component of the received scattered light, to deduce the conditions. This converter can avoid time consuming scanning of frequencies to obtain the Brillouin frequency spectrum, and avoids the heavy processing load of deducing a peak or average frequency from the spectrum. The converter can be implemented in the optical domain using a grating or interferometer, or in the electrical domain using a diplexer or electrical interferometer. It can generate complementary signals, having opposite signs, a ratio of these signals representing the frequency. This can avoid sensitivity to amplitude changes in the received scattered signals and provide common mode rejection of noise.

An antenna device corresponds to a plurality of radio communications systems and frequency bands, can simultaneously carry out a reception and a transmission of different radio communications systems, and is capable of using antenna diversity by a simple construction. An antenna device comprises a first antenna matching with first, second, and third frequency bands, a second antenna matching with the third frequency band, a diplexer and the like. For signals of the first frequency band, a high-frequency switch circuit connects a transmitter or a receiver to the diplexer by switching. For signals of the second frequency band, an additional high-frequency switch connects a receiver or a transmitter to the diplexer by switching. For signals of the third frequency band, the additional high-frequency switch circuit and a further additional high-frequency switch circuit connect the second antenna or diplexer to a transmitter / receiver by switching.

A radiometric heating / sensing probe for radiating electromagnetic waves of a first frequency capable of heating tissue and detecting electromagnetic waves of a second frequency emitted by the tissue indicating tissue temperature. The probe includes a dual frequency antenna, a signal transmitting path to the antenna and a signal receiving path from the antenna to a radiometer. A diplexer connected between those paths inside the probe includes a quarter wave stub in the form of a shorted slab line-type transmission line in the signal transmitting path. The entire probe package is only about 0.4 in. long and 0.08 in. in diameter so that it can be used in many minimally invasive applications.