Abstract: A method and apparatus for simplifying a structure needed to delay data in delay units when a reference signal and data are transmitted by using chaotic signals are provided. The method includes delaying data by at least two delay times, wherein each of the delay times occurs sequentially; multiplexing the data, which has been delayed, according to a control signal; and transmitting the data and a reference signal which corresponds to the data at an interval of delay time. The apparatus includes a first delay unit which is configured to delay data for a first delay time; a second delay unit which is configured to delay the data output from the first delay unit for a second delay time; and a multiplexer which is configured to multiplex the data from the first and second delay units according to a control signal.

Abstract: An ultra wideband antenna is provided that filters a predetermined frequency signal. The ultra wideband antenna includes a power feeding part that receives a supply of an external electromagnetic energy; a radiator excited by the electromagnetic energy fed through the power feeding part and radiating an electromagnetic wave; and a stub, provided on the radiator in a direction parallel to a direction of an electric field formed by the electromagnetic wave, that intercepts transmission/reception of a predetermined frequency band signal. The length of the stub may be ¼ of a wavelength of the intermediate frequency of the predetermined frequency band to be removed to filter the corresponding frequency band signal. The ultra wideband antenna simplifies the construction of an ultra wideband receiving system with the power loss and noise characteristics of the system improved.

Abstract: Provided are an on-chip balun, a transceiver using the on-chip balun, and a method for fabricating the on-chip balun. The on-chip balun includes: a first metal winding including a port grounded and a port to which an unbalanced signal is input; a second winding outputting an induced current generated by the first metal winding as two signals having about equal intensity and a phase difference of about 180°; and a ground shield positioned between the first and second metal windings and having a symmetric structure so as to generate a symmetric parasitic capacitance between the ground shield and the second metal winding. The ground shield can be inserted between the first and second metal windings to remove an asymmetrical parasitic capacitance so as to reduce a phase imbalance and a gain imbalance of an output value of the second metal winding. As a result, a highly balanced on-chip balun can be fabricated.

Abstract: Provided are a wide band-differential chaos shift keying modulation method, a transmitting apparatus adopting the wide band-differential chaos shift keying modulation method, a wide band-differential chaos shift keying demodulation method, and a receiving apparatus adopting the wide band-differential chaos shift keying demodulation method. The wide band-differential chaos shift keying modulation method includes: generating a wide band chaotic signal; delaying the wide band chaotic signal; multiplying the delayed wide band chaotic signal by an information signal to output a multiplied signal; and performing a switching operation so as to alternately transmit the wide band chaotic signal and the multiplied signal. Thus, the invention can be realized without an APLL, a mixer, an FM modulator, and the like, to reduce power consumption and manufacturing cost for the transmitting apparatus.

Abstract: An apparatus and method for compensating for the frequency offset of a received signal in a receiving apparatus of a mobile communication system. In the present invention, a sine component is calculated by adding I and Q channel signals resulting from downconverting a training sequence inserted between data symbols, and a cosine component is calculated by subtracting the Q channel signal from the I channel signal. Using the cosine and sine components at two time points, tangent components for the two time points are computed and thus first and second phase values are obtained. The frequency offset is estimated by determining the slope of a second-order line derived from the first and second phase values. The frequency offset of the received signal is compensated for based on the estimated frequency offset.

Abstract: Disclosed is a local oscillation circuit for a direct conversion receiver, which includes a local oscillator for outputting a local oscillation signal of a predetermined frequency; and a fractional signal generator for converting the local oscillation signal into a fractional harmonic signal, which has a frequency equal to a frequency of a received signal, and outputting the converted signal to a down converter. The fractional signal generator includes a divider for dividing a frequency of an output signal of the fractional signal generator by a predetermined integer; and a mixer for mixing the local oscillation signal and an output signal of the divider.

Abstract: A shredded parallel stacked inductor is provided. The shredded parallel stacked inductor includes a substrate, an oxide film formed on the substrate, metallic layers spirally formed within the oxide film, and vias formed in regions of the metallic layers to join the metallic layers in parallel, thus forming a spiral cavity in a center part of the metallic layers.

Abstract: A programmable surface acoustic wave filter and methods thereof including a piezoelectric substrate, a ground electrode formed in a comb structure on the piezoelectric substrate, a plurality of output electrodes formed in comb structures on the piezoelectric substrate and alternately disposed together with the ground electrode, and a switching unit performing a switching operation so as to selectively transmit output signals output from the plurality of output electrodes to an output node. As a result, a filtering characteristic of the programmable surface acoustic wave filter can be programmed in a desired format.

Abstract: An apparatus and method for generation of a noise signal are provided. The apparatus includes a noise synthesizing module and a noise signal transfer module. The noise synthesizing module includes a voltage controlled oscillator, a phase frequency detector, a phase locked loop filter, and a reference generator which form a phase locked loop. An output signal of the reference generator is provided to a first phase-frequency input of the phase-frequency detector, and an output signal of the voltage controlled oscillator is provided to a second input of the phase-frequency detector. An output signal of the phase-frequency detector is provided to an input of the phase locked loop filter, and an output of the phase locked loop filter is provided to a frequency control input of the voltage controlled oscillator.

Abstract: Disclosed is a technique for obtaining an_estimate and variance of each variable based on a constraint manifold. Particles (or samples) are sampled in order to filter and fuse ambiguous data or information on at least one state variable of a system using the particles. The sampling is carried out in consideration of an influence which non-linearity of the constraint manifold of_a system model, an observation model or another system model exerts on a probability distribution of the state variable. With this construction, it is possible to reduce decrease of fusion and filtering performance, decrease a Gaussian approximation error, and detect mismatched information.

Abstract: An analog correlator for very high speed data communication, including a single transmission line receiving an input signal and used as a signal delay circuit, a plurality of analog multipliers connected in parallel with a predetermined gap from the transmission line, for receiving a predetermined size of voltages, respectively, and an adder for adding the signals from the plurality of analog multipliers and transmitting the resultant signal as an output signal. The analog correlator can perform very high speed data communication, and can be applied to a high precision position estimation system. Moreover, the time delay is controlled in each part of the transmission line by adjusting a size of a variable capacitor. As a result, the length of the transmission line can be adjusted. Furthermore, the correlator is adaptively used according to variations of the very high speed communication environment by adjusting voltages of application voltage devices.

Abstract: An integrated circuit having integrated inductors includes at least one pair of transistors, and at least one inductor group which includes a pair of inductors coupled to the at least one pair of the transistor, respectively. The pair of the inductors form a spiral shape on a plane and the inductors arranged symmetrically to each other. Magnetic fluxes, which are generated by current flows along the inductors of the at least one inductor group, are formed in a direction to mutually intensify the magnetic fluxes according to differential signals applied to the at least one transistors from outside. Accordingly, high inductance and high quality factor can be attained owing to the positive magnetic coupling of the inductors.

Abstract: An ultra wide band antenna having a 270° coverage and a system thereof. The ultra wide band antenna includes a dielectric substrate, two Vivaldi horn radiators attached to the dielectric substrate and including central axes orthogonal to each other, and a single radiator coupled to the two Vivaldi horn radiators. The ultra wide band antenna system includes: a first ultra wide band antenna including a dielectric substrate, two Vivaldi horn radiators attached to the dielectric substrate and including central axes orthogonal to each other, and a single radiator coupled to the two Vivaldi horn radiators; and a second ultra wide band antenna including a dielectric substrate, two Vivaldi horn radiators attached to the dielectric substrate and including central axes orthogonal to each other, and a single radiator coupled to the two Vivaldi horn radiators, positioned on an identical plane to the first ultra wide band antenna, and forming a line symmetric structure together with the first ultra wide band antenna.

Abstract: An ultra wide band (UWB) antenna with a unidirectional radiation pattern, including: a power feeder including a connecting point at one end and a feeding point at the other end; and a radiator including a dipole part, connected with the feeding point on the basis of the feeding point, and a loop part, whose both ends are connected with both ends of the dipole part respectively to be closed-loop-shaped. Accordingly, a UWB antenna with a unidirectional radiation pattern which mainly performs radiation perpendicular to an antenna plane can be provided.

Abstract: A quadrature voltage controlled oscillator having low phase noise and excellent output swing characteristics includes a first voltage controlled oscillator for outputting a positive in-phase output signal and a negative in-phase output signal; a second voltage controlled oscillator for outputting a positive quadrature-phase output signal and a negative quadrature-phase output signal, the second voltage controlled oscillator having a symmetrical structure with the first voltage controlled oscillator and constituting a feedback loop together with the first voltage controlled oscillator; a first constant current source for supplying constant current to the first voltage controlled oscillator in response to the output signals; and a second constant current source for supplying constant current to the second voltage controlled oscillator in response to the output signals.

Abstract: Provided are a terminal performing a wake-up with consumption of low power and a wake-up method performed by the terminal. The terminal includes: a passive filter outputting a correlation signal between a received signal and a reference signal; and a wake-up controller controlling whether to wake up a communication module, using the correlation signal output from the passive filter. Thus, a wake-up signal can be processed using the passive element that does not consume power during its operation. Also, a wake-up of a communication module can be controlled using the result of processing the wake-up signal. As a result, power consumption can be greatly reduced during the wake-up.

Abstract: A small-sized on-chip complementary metal-oxide semiconductor (CMOS) Power Amplifier having improved efficiency is provided herein. The on-chip CMOS power amplifier is capable of improving efficiency and maximizing output thereof by enhancing a K factor, which may cause a problem in a power amplifier having a distributed active transformer structure. The on-chip CMOS power amplifier having an improved efficiency and being fabricated in a small size, the on-chip CMOS power amplifier includes a primary winding located at a first layer, secondary windings located at a second layer, which is an upper part of the first layer, the secondary windings being located corresponding to a position of the primary winding, and a cross section for coupling the second windings with each other.

Abstract: A space-time multiuser detector simultaneously reduces multiple access interference (MAI) and multipath channel distortion (MCD) that are disadvantages of mobile communication systems. The space-time multiuser detector includes a plurality of receiving antennas; a channel estimator which estimates signals received via the receiving antennas; a space-time diversity decoder which performs space-time decoding with respect to the signals provided from the channel estimator and performs diversity combination; a signal aligner which aligns the signals provided from the space-time diversity decoder; and a successive interference cancellation detector which generates an interference signal from the signals that are provided from the signal aligner one by one in sequence, and removes the interference signal from the received original signals.

Abstract: An active inductor capable of tuning a self-resonant frequency, an inductance, a Q factor, and a peak Q frequency by applying a tunable feedback resistor to a cascode-grounded active inductor is disclosed. The tunable active inductor includes a first transistor having a source connected to a power supply voltage and a gate connected to first bias voltage; a second transistor having a drain connected to a drain of the first transistor and a gate connected to a second bias voltage; a third transistor having a drain connected to a source of the second transistor and a source connected to a ground voltage; a fourth transistor having a drain connected to a gate of the third transistor, a source connected to the ground voltage and a gate connected to a third bias voltage; a fifth transistor having a source connected to the drain of the fourth transistor and a drain connected to the power supply voltage.

Abstract: Disclosed is a dual-band voltage-controlled oscillator using bias switching and output-buffer multiplexing. The dual-band voltage-controlled oscillator includes a power supply unit for supplying a source voltage; plural voltage-controlled oscillation units for outputting different oscillation frequencies according to controls of a certain tuning voltage; plural bias units for generating driving voltages for driving the voltage-controlled oscillation units and supplying the driving voltages to the voltage-controlled oscillation units; and plural buffers for selectively outputting oscillation frequencies of the plural voltage-controlled oscillation units. The present invention implements the dual-band voltage-controlled oscillator through bias switching and output-buffer multiplexing, which brings an advantage of elimination of interference between output frequencies to enhance phase noise characteristics.