摘要:
Beamforming to image an object (310), such as an interventional tool, is enhanced by initializing the beamformer (308) with the object's location, and optionally its orientation. The initializing uses an estimate of the location/orientation. The estimate is derived from the output of one or more sensors (304, 306). These are disposed external to the imaging array (316) that operates with the beamformer. The estimate is made without the need for a result of any imaging based on data arriving by reflected ultrasound. One or more of the sensors may be attached to the object, which may be elongated, as in the case of a needle or catheter used in medical diagnosis and treatment. In some implementations, one or more of the sensors are attached to the imaging probe (302). The sensors may be, for example, ultrasound, electromagnetic, optical, or shape sensors. Alternatively, ultrasound transmitting transducers may be substituted for the ultrasound sensors.
摘要:
In one aspect, an ultrasound receive beamformer (212) is configured for one-way only beamforming (112) of transmissive ultrasound using one-way delays. The receive beamforming in some embodiments is used to track, in real time, a catheter, needle or other surgical tool within an image of a region of interest. The tool can have embedded at its tip a small ultrasound transmitter or receiver for transmitting or receiving the transmissive ultrasound. Optionally, additional transducers are fixed along the tool to provide the orientation of the tool.
摘要:
The present invention relates to a band rejection filter. The band rejection filter includes a first signal transmission channel called a direct channel and a second signal transmission channel called a secondary channel. The direct channel and the secondary channel being designed to introduce at a first rejection frequency a phase difference of 180° between the signal circulating via the direct channel and the signal circulating via the secondary channel. Additionally, the secondary channel includes a filtering element for which the cut-off frequency is different from the first rejection frequency in a way to create a second rejection frequency.
摘要:
An ultrasonic diagnostic imaging system produces an image with an extended focal range by transmitting a plurality of beams spaced along an array for multiline reception. The receive multilines of a plurality of transmit beams are spatially aligned and are combined with phase adjustment between the respective receive multilines to prevent undesired phase cancellation. The combined multilines produce the effect of an extended transmit focus so that an image produced using the combined multilines exhibits an extended focal range. To prevent motion artifacts the multiline order is adjustable as a function of image motion.
摘要:
The present invention relates to a diversity antennas system comprising at least two antennas of the dipole type each formed by a first and a second conductive arm, supplied differentially wherein the two antennas comprise a common arm called first arm forming at least one cover for an electronic card and each one a second arm mounted in rotation at one extremity of the first arm.
摘要:
An ultrasonic diagnostic imaging system produces an image with an extended focal range by transmitting a plurality of beams spaced along an array for multiline reception. The receive multilines of a plurality of transmit beams are spatially aligned and are combined with phase adjustment between the respective receive multilines to prevent undesired phase cancellation. The combined multilines produce the effect of an extended transmit focus so that an image produced using the combined multilines exhibits an extended focal range. To prevent motion artifacts the multiline order is adjustable as a function of image motion.
摘要:
The antenna, particularly for portable televisions, comprises two ports coupled to a radiating element (11), the two ports being placed on the radiating element at 90° to each other and at 45° relative to a horizontal plane. The two ports are linked to a broadband switching and phase shifting circuit controlled in order to supply a polarization diversity signal as output.
摘要:
The present invention concerns a system of receiving signals comprising a retransmission base to amplify signals captured at a point in a domestic environment and retransmit them at the same frequency to digital receivers of the said domestic environment. According to the invention, the retransmission base amplifies and retransmits up to N DVB-T channels the positions of which can be anywhere in the receive band and are chosen dynamically by the system users. Means are provided in the system to share the system's amplification resources between the system's various digital receivers.
摘要:
The antenna, particularly for portable televisions, comprises two ports coupled to a radiating element (11), the two ports being placed on the radiating element at 90° to each other and at 45° relative to a horizontal plane. The two ports are linked to a broadband switching and phase shifting circuit controlled in order to supply a polarization diversity signal as output.
摘要:
The invention provides a dielectric resonator oscillator DR, especially for transmission devices whose oscillating frequency may take several values. The oscillator uses two interfering conductors 30 and 31 switched so that they may or may not form a metal plane close to the dielectric resonator DR in order to vary the frequency of the oscillator while using a single resonator. The interfering conductors 30 and 31 are located in the cavity CAV close to the resonator DR and the switching means may or may not establish an electrical contact between the said interfering conductors 30 and 31.