Samsung Electronics Co., Ltd.

Toyota Jidosha Kabushiki Kaisha

Takahiko Kishi

Hiroki Okada

Satoshi Suzuki

Tomoyoshi Yasue

Jun-ichi Takada

A wireless device includes a baseband unit and front-end units that are provided in individual housings. The baseband unit and the front-end units are connected to each other by wire. A transmitter for synchronization that converts a signal based on a reference clock into a radio signal and transmits the radio signal as a clock synchronization signal is provided in any one of the housings, and receivers for synchronization that receive the signal for the clock synchronization and PLLs that generate a clock synchronized with a reference clock signal which is obtained from the received clock synchronization signal are provided in the housings other than the housing having the transmitter provided therein. In order to simultaneously process a plurality of wireless devices having different symbol rates, it is preferable to provide the transmitter, the receiver, and the PLL for each reference clock.

Synchronization of front-end and baseband units in wireless communications device by wirelessly transmitting clock signal therebetween

A cardiac signal processing apparatus includes: a unit for acquiring, from a heartbeat sensor, cardiac signals relating to heartbeats of a subject; a low-pass filter for allowing passage of those cardiac signals having a first predetermined frequency or lower, among the cardiac signals; higher harmonic noise acquisition unit for acquiring harmonic signals of low-frequency noise by performing high frequency extrapolation on the signals output from the low-pass filter; a high-pass filter for allowing passage of those cardiac signals having a second predetermined frequency or higher, among the cardiac signals; and higher harmonic noise removal unit for removing the harmonic signals of low-frequency noise from the signals output from the high-pass filter. It is thus made possible to remove noise from the cardiac signals and to obtain desirable heartbeat detection characteristics.

Cardiac signal processing apparatus and cardiac signal processing method

Disclosed is a receiver for achieving optimum power consumption and optimum reception performance according to use, purpose, and required performance. A control circuit calculates an evaluation value H relating to a detection method and a reception state of a received signal. When a delay detection is selected depending on the evaluation value H, a delay detection circuit and a judgment circuit operate, and a selection circuit selects and outputs an output signal of the judgment circuit. When a semi-synchronous detection is selected depending on the evaluation value H, the semi-synchronous detection circuit, the signal judgment unit and the differential decoder operate, and the selection circuit selects and outputs an output signal of the differential decoder. When a dynamic controlled detection is selected depending on the evaluation value H, the delay detection and the semi-synchronous detection are controlled to be dynamically changed.

Receiver

An automatic gain control device capable of reducing signal saturation or signal distortion caused by out-of-band signals of a filter or delay of a control signal. An AGC response control section compares a level of control voltage ('V_I terminal' signal) output from an AGC control section b with a level of control voltage ('V_I terminal' signal) output from an AGC control section c. If the &#x2018;V_I terminal&#x2019; signal is below the &#x2018;V_I terminal&#x2019; signal, an AGC amplifier is controlled by the &#x2018;V_I terminal&#x2019; signal. If the &#x2018;V_I terminal&#x2019; signal is above the &#x2018;V_I terminal&#x2019; signal, the AGC amplifier is controlled by the &#x2018;V_I terminal&#x2019; signal. In the latter case, control information of the AGC control section b is replaced by control information of the AGC control section c so that the AGC control section c controls the AGC amplifier c.

Automatic gain control device

A digital frequency converter is provided that maintains a high power efficiency in an EER scheme despite the inclusion of digital signal processing. An inputted modulated signal is converted into phase information and amplitude information of a polar coordinate type. The amplitude information is outputted as amplitude information of the digital frequency converter. Meanwhile, phase change of a frequency f, which is outputted from an accumulator, corresponding to lower 'Q' figures of phase data PD for frequency conversion is added to the phase information by an adder. In addition, a sampling frequency of the phase information outputted from the adder is upsampled by an interpolator, and also, phase change of a frequency f, is converted into a phase-modulated signal of an orthogonal coordinate type, and then outputted as phase information of the digital frequency converter.

Digital frequency converter

Disclosed is radio equipment for transmission and reception of Frequency Division Duplex mode signals and transmission signal characteristic compensation utilizing small-scaled circuit construction. A receiver converts Radio Frequency band signals from an antenna sharer to an Intermediate Frequency (IF) via a mixer and into digital signals utilizing an Analog-to Digital Converter. Reception signals and image signals of transmission signals, both having an IF A are contained in the converted signals, are converted into reception signals having an IF B and image signals having an IF C, respectively, which both have positive and negative carrier frequencies symmetrical to a zero frequency direct current component and are represented as a complex number. A transmitter converts the IF C into a baseband of image signals, and compensates signal characteristics relative to complex baseband signals of quantized transmission signals at a characteristic compensator using converted signals as reference signals.

Radio equipment using image signals for compensating transmission signals

A numerical control oscillator (NCO) for reducing a circuit size and power consumption while maintaining a desired frequency deviation, and suppressing generation of a spurious as much as possible. The NCO comprises a phase accumulator for accumulating input phase difference data to generate phase data, and a read only memory (ROM) for storing a phase/amplitude conversion table to output amplitude data corresponding to the phase data generated by the phase accumulator. The phase accumulator includes a phase register and a phase calculator. If a sampling frequency of an output signal from the NCO is Fs, the upper limit of a desired frequency setting interval of the output signal is FD and K and L are arbitrary integers, the phase calculator adds or subtracts the input phase difference data and phase data from the phase register to or from each other by a modulo operation taking the nearest integer of M as a modulus, where M=Fs/FD&#xd7;K/L. The ROM has its address terminal connected to an output terminal of the phase accumulator. On the basis of the stored phase/amplitude conversion table, the ROM outputs amplitude data corresponding to phase data, input from the phase accumulator to the address terminal, through its data terminal as an output signal of the NCO set to a frequency setting interval of a dF step, where dF=FD/K&#xd7;L.

Numerical control oscillator, digital frequency converter and radio frequency unit

Disclosed are a wireless phone and a wireless communication method wherein communication quality estimation is made for both circuit switching and packet communication modes and sound of both the modes is interpolated mutually so as to improve the sound quality. The switching between first and second sound signals is performed at intervals of a speech pitch period based on quality information of first and second sound signals, where the first and second signals are received and decoded, respectively, through a first wireless communication in circuit switching mode and a second wireless communication in packet communication mode. A delay control signal is outputted to compensate for the time difference between the first and second sound signals, based on the quality information of the two sound signals, and the time difference is compensated for based on the delay control signal.

Wireless phone and wireless communication method

A multichannel receiver for effectively receiving multichannel signals at the same time without any restrictions in the symbol timing and channel interval of modulated signals. A quadrature detector of the multichannel receiver includes first and second multipliers. The first multiplier multiplies a received signal by a real number axis signal generated from a quadrature carrier oscillator. The second multiplier multiplies a received signal by an imaginary number axis signal. The quadrature detector converts a carrier of a center signal of odd signals into a DC component of zero frequency, and converts the center signal into a complex baseband signal, and at the same time converts carrier signals other than the center carrier signal into a complex IF signal symmetrical to the DC component of zero frequency. ADCs (Analog-to-Digital Converters) convert the complex IF signals into complex IF digital signals. The complex IF digital signals are applied to a first group of complex mixers and a second group of complex mixers at the same time. The complex mixers correspond to individual channels, and their local signal frequencies have a complex conjugate relation to each other. The complex mixers perform frequency conversion on their reception signals, and thus generate complex baseband signals.

Multichannel receiver for simultaneously receiving a plurality of different channel signals

Radio equipment including a characteristic compensator for compensating for an orthogonality error of a mixer with low consumption power is disclosed. In radio equipment, an orthogonal detector converts a received real signal into a complex reception signal of an intermediate frequency. Further, when a complex reception signal converted into a digital signal by A/D converters includes a desired signal (quasi-desired signal), which includes an image signal of a non-desired signal, and a non-desired signal (preparatory desired signal), which includes an image signal of a desired signal, a frequency of the quasi-desired signal is frequency-converted to a signal closer to a direct current component by a frequency converter and a frequency of the preparatory desired signal is frequency-converted to a signal closer to a direct current component by a frequency converter. A decimator respectively performs a filtering and a down-sampling on the frequency-converted quasi-desired signal and preparatory desired signal. A characteristic compensatorsuppresses the image signal of the non-desired signal included in an inputted quasi-desired signal by means of a complex codomain signal of an inputted preparatory desired signal.

Radio equipment

Disclosed is an automatic gain controller capable of reducing signal saturation or signal distortion caused by out-of-band signals of a filter extracting an object signal or delay of a control signal and capable of precisely measuring a signal level in a filter band. An AGC response control section compares a level of control voltage ('V_I terminal' signal) outputted from a first AGC control section and inputted into a 'V_I terminal' with a level of control voltage (&#x201c;V_I terminal&#x201d; signal) outputted from a second AGC control section and inputted into a &#x201c;V_I terminal&#x201d;. If the control voltage, which is the &#x201c;V_I terminal&#x201d; signal, outputted from the second AGC control section is less than the control voltage, which is a &#x201c;V_I terminal&#x201d; signal, outputted from the first AGC control section, the AGC response control section controls an AGC amplifier by using the control voltage outputted from the second AGC control section. If the control voltage, which is the &#x201c;V_I terminal&#x201d; signal, outputted from the second AGC control section is greater than the control voltage, which is the &#x201c;V_I terminal&#x201d; signal, outputted from the first AGC control section, the AGC response control section controls the AGC amplifier by using the control voltage outputted from the first AGC control section.

Automatic gain controller

Disclosed is a frequency converter with an excellent frequency characteristic, having a minimized number of multipliers. A digital down-converter includes a decimator/mixer, an interpolator and a channel filter. The decimator/mixer performs quadrature conversion from a real signal to complex signals, frequency conversion by a frequency K&#x3c9;, and 1/(M&#xd7;I)-fold decimation on a signal obtained by sampling an RF/IF signal S(i) by an A/D converter. The interpolator is comprised of I-fold up-samplers and lowpass filters, and performs I-fold interpolation on the outputs from the decimator/mixer. The channel filter is comprised of lowpass filters having a band characteristic given to a communication channel, and outputs band-rejected baseband signals i(j) and q(j) by filtering the outputs of the interpolator.

Frequency converter

There is provided a frequency converter for suppressing generation of an image signal using a simple adaptive algorithm. In the frequency converter, an orthogonal converterconverts an RF/IF signal to a complex signal along with frequency conversion and ADCs quantize the complex signal. An image signal canceller achieves the complex conjugate of the quantized complex signal by inverting the imaginary part of the quantized signal through a multiplier. An LMS core adaptively processes the complex signal using the complex conjugate signal as a reference signal and the output of the image signal canceller as an error signal. The resulting cancellation signals are level-matched in attenuators. Subtracters combine the complex signal with the level-adjusted complex conjugate signal.

A frequency synthesizer that improves a unique DDS characteristic, while maintaining a circuit scale (ROM size) of a direct digital synthesizer (DDS). A first digital signal generator generates a quantized frequency signal, and a second digital signal generator generates a frequency signal having a fine frequency resolution and many spurious signals as compared with the first digital signal generator. A filter performs band rejection on an output of the second digital signal generator, and a mixer mixes an output of the first digital signal generator with an output of the filter.

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Yokohama, Japan

Takahiko Kishi