Abstract: A magnetic resonance coil apparatus is provided, the apparatus having a posterior coil unit including a base unit and a further coil component, wherein the further coil component is arranged so as to be able to be tilted on the base unit with respect to the base unit and wherein the posterior coil unit includes a position acquisition unit.

Abstract: One embodiment of the present invention sets forth a wireless communications system configured to efficiently operate within an arbitrarily and uniquely defined set of channels. Each one of the set of channels has an assigned digital radio transceiver instance configured to operate according to transmission requirements that are unique to the corresponding channel. A set of digital radio transceiver instances comprises a meta-transceiver, which enables communications to one or more other devices via one or more digital radio transceiver instances.

Abstract: The carrier phase of a carrier wave modulated with information symbols is recovered with a multi-stage, feed-forward carrier phase recovery method. A series of digital signals corresponding to the information signals is received. For each digital signal, a coarse phase recovery is performed to determine a first phase angle which provides a first best estimate of the information symbol corresponding to the digital signal. Using the first best estimate as input, a second stage of estimation is then performed to determine a second phase angle which provides an improved (second) best estimate of the information symbol. Additional stages of estimation can be performed. The multi-stage, feed-forward carrier phase recovery method retains the same linewidth tolerance as a single-stage full blind phase search method; however, the required computational power is substantially reduced. The multi-stage, feed-forward carrier phase recovery method is highly efficient for M-QAM optical signals.

Abstract: The present invention relates to a method and apparatus for transceiving data. A method in which a transmitting terminal transmits data to a receiving terminal in a MIMO system according to one embodiment of the present invention comprises the following steps: generating a data field containing the data; generating a signal field containing information on the data field; generating a data frame containing the data field and the signal field; and transmitting the data frame to the receiving terminal. According to the present invention, an end of the frame being transmitted is accurately notified to the receiving terminal in a communication system in which the frame is transmitted using MIMO, thereby decoding the frame in a more efficient manner at the receiving terminal.

Abstract: A multilevel QAM demodulator includes a phase difference calculation unit calculating a phase difference signal based on the common phase signal and orthogonal signal after the phase rotation compensation, a phase shift amount calculation unit calculating a phase shift amount indicating a degree of a phase shift based on the common phase signal and orthogonal signal after the phase rotation compensation and phase noise compensation, and a correction unit correcting the phase difference signal based on the phase shift amount. A phase rotation is performed for the phase noise compensation based on the phase difference signal corrected by the correction unit.

Abstract: Mitigation of interference effects in certain wireless communications is accomplished by the disclosed method. A wireless communications device communicates utilizing a protocol which requires hopping from channel to channel within a communications frequency band while transmitting. Operating according to the disclosed method, the device scans the available communications channels and identifies channel(s) experiencing interference from other transmitting devices. When hopping to such identified channels, the device transmits only null packets, thus avoiding the need to re-transmit packets due to interference and mitigating the effects of such interference on the communications data rate.

Abstract: Methods and systems are provided for estimating the DC offset distortion in a receiver. A fast Fourier transform is applied to at least a portion of a preamble portion of the received signal; an impact of the DC offset distortion on one or more empty subcarriers is determined; individual DC estimates are derived based on each of the determinations; and each of the individual DC estimates are combined to obtain an overall DC estimate.

Abstract: A received low-frequency standard radio wave, which is an amplitude modulation signal, is converted to an intermediate frequency signal Sa, and is output to a detection circuit and an AGC circuit. The detection circuit and AGC circuit generates an RF control signal Sf1 and IF control signal Sf2 from the input intermediate frequency signal Sa, and controls an RF control circuit and IF control circuit by outputting the generated RF control signal Sf1 and IF control signal Sf2 to the RF control circuit and IF control circuit. By this a radio wave reception device can speed up AGC operation.

Abstract: A communications apparatus is capable of being disposed in-line in a communications link that supports a main communications channel. The communications link connects a first host to a second host. The communications apparatus comprises an application logic that supports a sub-channel within the main channel. When the main channel is potentially faulty, the application logic is arranged to monitor the main channel to determine an error condition and send a message by replacing data reserved for control purposes in order to communicate the error condition as sub-channel data.

Abstract: The invention relates to an orthogonal frequency division multiplexing system with PN-sequence. In the synchronization of the invention, both timing offset and frequency offset are estimated and compensated by utilizing a time and frequency synchronization device. In addition, the PN-sequence with the cyclic prefix is added to the OFDM symbol before transmitting. The time and frequency synchronization device of the invention comprises two synchronization circuits from the cyclic prefix and PN-sequence when calculating the timing offset and frequency offset of receiving signal. As a result, the OFDM system of the invention not only has better performance in fading channel, but also has the better bandwidth utilization without extra bandwidth for transmitting the PN-sequence.

Abstract: A frequency offset correcting unit estimates frequency offsets in a preamble period, corrects digital received signals by the estimated initial frequency and further corrects them by residual frequency signals. A receiving weight vector computing unit computes receiving weight vector signals by using LMS algorithm. Based on the error vectors or receiving weight vector signals derived by LMS algorithm, the frequency offsets contained in corrected received signals are also estimated and are outputted as the residual frequency signals. A multiplier weights the corrected received signals with the receiving weight vector signals. An adder sums up outputs of the multiplier so as to output a synthesized signal.

Abstract: A received low-frequency standard radio wave, which is an amplitude modulation signal, is converted to an intermediate frequency signal Sa, and is output to a detection circuit and an AGC circuit. The detection circuit and AGC circuit generates an RF control signal Sf1 and IF control signal Sf2 from the input intermediate frequency signal Sa, and controls an RF control circuit and IF control circuit by outputting the generated RF control signal Sf1 and IF control signal Sf2 to the RF control circuit and IF control circuit. By this a radio wave reception device can speed up AGC operation.

Abstract: Embodiments of an apparatus for sample rate conversion are described. Various embodiments include an interpolator configured to interpolate a digital input data stream by using values of an interpolation phase shift control quantity to generate a digital output data stream, a computing stage configured to compute values of the interpolation phase shift control quantity, and an enabling/disabling stage configured to selectively disable the interpolator while keeping the computing stage enabled.

Abstract: A method is provided for performing a clear channel assessment in a local device. The local device receives signal energy in a wireless channel and splits the received signal energy into a real portion and an imaginary portion. It determines a real portion of a squared signal energy by subtracting a squared imaginary portion of the signal energy from a squared real portion of the signal energy, and determines an imaginary portion of the squared signal energy by calculating twice the product of the real and imaginary portions of the signal energy. It can perform a signal detection function on the real and imaginary portions of the squared signal energy to produce a clear channel assessment signal that indicates whether a set signal type is present in the wireless channel. This clear channel assessment signal can be used to determine whether the local device should remain in a low-power mode.

Abstract: An information recording device in which low-noise and clear image or audio information can be recorded by stopping the generation of a carrier in an oscillation section of wireless communication device during an imaging or sound recording process.

Abstract: This invention offers a signal-off detection circuit allowing arbitrary setting of an issuing time (response time) of a signal disconnection alarm without being affected by a time constant of a direct current feedback circuit giving an offset voltage to an amplifier for amplifying a data signal. Input data signals per a fixed time determined by a timer is counted by a counter, and a count value is compared with a predetermined set value in a comparator. A configuration is made such that a signal disconnection alarm may be issued by detecting a disconnection state of the data signal according to a comparison result. Thereby, an issuing time of a signal disconnection alarm can be set without being affected by a time constant of a direct current feedback circuit giving an offset voltage to an amplifier for amplifying a data signal of a preceding stage.

Abstract: A method and system for conserving power in a WLAN receiver is provided by a channel estimator for detecting transmitted errors in a transmitted packet and providing equalization for the detected channel errors; a separate pilot processor for detecting off set errors from the channel estimation and providing off set correction to said equalization for the whole data portion of the packet after the preamble and a control response to the start of each packet for enabling said channel estimator during the preamble and thereafter disabling said channel estimator for the remainder of the packet and storing the estimated value.

Abstract: A method of conditioning a signal being communicated between a system to be controlled and a controller may include monitoring an actual output signal and conditioning the actual output signal. The method also includes determining the difference between the actual output signal and the condition signal and causing the actual output signal to be filtered based on the relationship between the difference between the actual output signal and the conditioned signal.

Abstract: A first automatic phase control (APC) detection circuit generates an APC detection signal having normal polarity from an amplitude modulation signal and APC detection reference signal. A second APC detection circuit generates an APC detection signal having reverse polarity from the amplitude modulation signal and the APC detection reference signal. A switch selects the APC detection signal having normal polarity in case of normal modulation and selects the APC detection signal having reverse polarity in case of overmodulation.

Abstract: A computerized tomography (CT) system having an apparatus and method for receiving high data rate communication is disclosed herein. The apparatus includes a controlled variable attenuator for attenuating an encoded digital data signal having a wide range of power levels, a digital envelope detector for de-encoding the encoded digital data signal, a noise filtering circuit for filtering out the residual undesirable encoded signal components, and a feedback loop for maintaining a desired signal level such that the encoded digital data signal is converted to its pre-encoded state suitable for processing to generate a CT image.

Abstract: A detector of a carrier loss in a modem receiver of a fax transmission of a document, of the type includes a first calculator of the receive signal and a first comparator of this energy with respect to a threshold. The detector further includes means for adapting said threshold between each page of the transmitted document.