Abstract: A transmitter clips a transmission signal before transmission in order to reduce the strength of at least one peak of the transmission signal exceeding a predetermined threshold. The transmitter includes a clipper having a minimizer, a filter and an adder. The minimizer minimizes of a cost function with respect to an optimization signal, the cost function having weighted terms as a function of the optimization signal. The terms relate to an effective modulation distortion and an effective overshoot exceeding the predetermined threshold. The filter forms a clipping signal by filtering the optimization signal formed as a result of the minimization according to the spectrum emission mask requirements of the radio system. The adder subtracts the clipping signal from the transmission signal.

Abstract: A wireless communications device includes a first receiver and a second receiver. The first receiver is configured to receive a first wireless signal (such as a Bluetooth or WLAN signal), while the second receiver is configured to receive a second wireless signal (such as a UWB signal). In addition, the second receiver is configured to determine spectral characteristics of the first wireless signal. Based on these determined spectral characteristics, an interference detection module may identify interference in the first wireless signal.

Abstract: The present invention is related to a method and system for transmit power control in a multiple-input multiple-output (MIMO) wireless communication system. Both a transmitter and a receiver comprise multiple antennae for transmission and reception. The transmitter comprises a power allocation unit for controlling transmit power based on a feedback received from the receiver. The receiver comprises a channel estimator and a singular value decomposition (SVD) unit. The channel estimator generates a channel matrix from a signal received from the transmitter and the SVD unit decomposes the channel matrix into D, U and V matrices. The receiver sends a feedback generated based on output from the SVD unit to the transmitter for controlling the transmit power. The feedback may be one of an eigenvalue, a transmit power level or a power control bit or command. A hybrid scheme for selecting one of them based on channel condition may be implemented.

Abstract: The present invention is related to a method and apparatus for generating feedback information for transmit power control in a multiple-input multiple-output (MIMO) wireless communication system. Both a transmitter and a receiver comprise multiple antennae for transmission and reception. The transmitter comprises a power allocation unit for controlling transmit power based on a feedback received from the receiver. The receiver comprises a channel estimator and a singular value decomposition (SVD) unit. The channel estimator generates a channel matrix from a signal received from the transmitter and the SVD unit decomposes the channel matrix into D, U and V matrices. The receiver sends a feedback generated based on output from the SVD unit to the transmitter. The feedback may be one of an eigenvalue, a transmit power level or a power control bit or command. A hybrid scheme for selecting one of them based on channel condition may be implemented.

Abstract: There is provided a bias power supply for setting a collector bias current of a mixer transistor and a collector bias current of an oscillation transistor. When a control voltage is equal to or smaller than a first predetermined value, an output voltage of the bias power supply is set to be increased so that at least one of the collector bias current of the mixer transistor and the collector bias current of the oscillation transistor can be increased.

Abstract: Methods to optimize range of multicast signal communication in wireless communication applications that use range-enhanced techniques for directed signal communication. A multicast signal may be sent multiple times through each of a plurality of independent omnidirectional transmit antennas of a communication device to a plurality of other communication devices to improve packet error rate (PER) at a given range (i.e., SNR). More generally, the multicast message can be transmitted up to N times using up to N times using any set of N complex linearly independent N-dimensional transmit weight vectors vi, . . . , vN associated with N plurality of transmit antennas that meets the power constraint ?vi?2=1, i=0, . . . , N?1, where the vector vi, is used for the ith transmission of the multicast signal.

Abstract: A switch that selectively changes radio frequency signals includes at least three FETs, which are connected in series. The source electrodes or drain electrodes arranged at an intermediate stage have a width narrower than that of the source electrodes or the drain electrodes arranged at the initial and final stages. It is thus possible to lower the parasitic capacitance to ground at the intermediate stage and to thereby realize the switch having a high handling power.

Abstract: A dial system for steering wheel of an automobile includes two dials respectively mounted on the steering wheel and each having a first housing and a dial set received in the first housing. The dial set includes a number button and multiple functional buttons partially extending the first housing for being operated. A circuit board is received in the first housing for wirelessly transmitting signals when the buttons are operated. A second housing is mounted to the first housing to form a space for receiving the dial set and the circuit board. A battery seat with a battery is laterally inserted into the space for providing power to the circuit board. A controller is disposed on the automobile for receiving and processing the signals from the first dial and the second dial.

Abstract: A method and apparatus are provided for enabling a transmitter to have a substantially linear magnitude response and a substantially linear phase response. The transmitter includes first and second power amplifier drivers (PADs) having respective first and second non-linear phase responses. The first non-linear phase response is based on a first bias applied to the first PAD, and the second non-linear phase response is based on a second bias applied to the second PAD. The first and second PADs are coupled in parallel to provide a combined substantially linear phase response. According to an embodiment, the first and second PADs have respective first and second average input capacitances. Signal swings about the first and second biases vary the respective first and second average input capacitances, which may be combined to provide a combined average input capacitance that is substantially insensitive to the signal swings about the first and second biases.

Abstract: A phase locked loop (PLL) frequency synthesizer to produce a local oscillator signal for a transmitter for operation at a plurality of RF frequency bands that are disparate. The transmitter has an intermediate frequency that is a sizable fraction of the bandwidth of one or more of the RF bands. The transmitter includes at least one RF upconverter, each having a local oscillator input coupled to the frequency synthesizer.

Abstract: In a receiver, a mixer portion provided in a front-end portion thereof is built with two mixers with different input/output linearity characteristics and different current consumption. According to the electric-field strength of a received signal, or manually, one of the mixers is chosen to operate so that, when the electric-field strength is in an ordinary range, the mixer with a better input/output linearity characteristic is chosen to operate with lower current consumption and, when the electric-field strength is in a high range, the mixer that, despite operating with higher current consumption, exhibits a still better input/output linearity characteristic is chosen. The receiver thus operates with lower current consumption and lower signal distortion.

Abstract: A source binary code that complies with a source architecture is translated to a target binary code that complies with a target architecture. The target binary code includes a first target portion translated from a respective source portion of the source binary code. During execution of the target binary code on a processor that complies with a target architecture, it is determined whether to retranslate the source portion to produce a second target portion that is more optimized to the target architecture than the first target portion or to retranslate the source portion to produce a third target portion that is more optimized to the target architecture than the second target portion.

Abstract: A receiver (100) adjusts its overall gain based on the detected power level of an incoming signal. The receiver is built with two detectors (D1, D2) which operate with different detecting ranges within the dynamic range of the incoming signal. If the actual power level of the incoming signal falls within one of the resolving ranges, an automatic gain control adjusts the gain of the receiver to a corresponding gain value. If not, the resolving range of one of the two detectors is shifted and eventually reduced to cover the portion of the dynamic range in which the power level is comprised. The gain of the receiver is then temporarily adjusted and a new measurement is carried out by the detector using the new resolving range. The AGC then re-adjusts the gain of the receiver based on the measurement given by the modified detector.

Abstract: An apparatus and method for amplifying a radio frequency signal including, generating a plurality of shaped pulses utilizing a piecewise linearizer circuit, applying the plurality of shaped pulses to a first input of a radio frequency amplifier circuit, and injecting a radio frequency carrier into a second input of the radio frequency amplifier circuit. The apparatus comprises a piecewise linearizer (PWL) circuit coupled to the input of a Radio Frequency Digital to Analog Converter (RFDAC) operating as a signal amplifier.

Abstract: A television tuner includes: low band and high-band receiving units; a mixer that frequency-converts low-band television signals from the low-band receiving unit or high-band television signals from the high-band receiving unit; first and second switching diodes that couple the low-band or high-band receiving unit and the mixer to each other, respectively; and a transistor which applies a bias voltage to one end of each of the switching diodes. The emitter of the transistor is grounded and the collector is pulled up to a power supply through a resistor. ON/OFF of the switching diodes are switched to be opposite to each other. The other end of each of the switching diodes is connected to the collector through a first inductance element. The collector of the transistor is connected to one end of a second inductance element, and the other end of the second inductance element is grounded in a high-frequency manner.

Abstract: A system for wireless communication, particularly for receiving communication signals, said system comprising: A main antenna structure (330), said antenna structure adapted to receive a communication signal (325a) as a first internal signal; and an antenna cable, said antenna cable having a first end operationally coupled to said main antenna structure and a second end, said antenna cable including a main conductor (335) for passing said first internal signal, and a second receiving conductor (340), said second receiving conductor adapted to receive said communication signal as a second internal signal, and wherein said second receiving conductor as a receiving element is spatially separated from the main antenna structure. The disclosed antenna system and apparatus for the extraction of the second, spatially-separated received signal achieves spatial diversity to alleviate multipath effects in wireless communication systems.

Abstract: The linearity of a transmission signal is improved in a wireless communication device by adjusting a delay difference between paths of two signals that are combined into one after modulation through the paths of different delay amounts, such as an r signal and a ? signal in EER. A transmitter includes: a DA converter unit which converts, into analog signals, separated input digital signals; a combiner which combines the analog signals obtained through the DA conversion with each other; an distributor which extracts a feedback signal; an AD converter which converts the feedback signal into a digital signal; an oscillator unit which supplies clock signals to the converters; a first separation unit which separates the feedback signal; and a comparator unit which compares the input signal and the feedback signal, wherein the oscillator unit controls the output clock signals based on a result of the comparison.

Abstract: A transmitting apparatus includes a polar signal producing circuit which produces signals corresponding to the amplitude and the phase of a transmitting modulated wave from an input signal and multiplies the amplitude signal by the phase signal by a multiplying circuit to amplitude modulate a phase-modulated wave to produce a transmitting modulated wave and radiates this transmitting modulated wave as radio wave from an antenna. An amplitude/phase detecting circuit detects an amplitude signal and a phase signal from the input of the multiplying circuit and the input of a phase-modulated signal producing circuit.

Abstract: An adjacent interference removal device capable of providing an improved reception quality. An IF signal Sin having passed through an IF filter having a pass frequency band width of 200 kHz is supplied to a first narrow band filter having a pass frequency band width extending from a center frequency (carrier frequency) of the IF filter to +50 kHz, as well as to a second narrow band filter having a pass frequency band width extending from a center frequency (carrier frequency) of the IF filter to ?50 kHz.

Abstract: Many broadcast stations transmit their programs via a variety of different frequencies. The invention relates to monitoring alternative frequencies during the reception of a broadcast signal at a present frequency. Whenever the broadcast signal at an alternative frequency is checked, the receiver's gain is instantaneously switched from a present gain value corresponding to the present frequency to a second gain value corresponding to the alternative frequency. The second gain value is adapted to the supposed signal strength of the broadcast signal at the alternative frequency.