Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Socionext Inc.

Shunsuke Hirano

Hisashi Adachi

Hiroyuki Yoshikawa

Hiroaki Kosugi

Toshifumi Nakatani

Masakatsu Maeda

Yasunori Miyahara

Takayuki Tsukizawa

Yosuke Mitani

Ryoichi Yamada

Kaoru Ishida

Yoshihiro Hara

Takashi Miyazaki

Toru Matsuura

Koji Takinami

Kenji Miyanaga

Shigeru Morimoto

Kenta Aruga

Yuji Saito

Daisuke Kimura

Hiroshi Haruki

Mamoru Arayashiki

Yukio Hiraoka

Takahito Miyazaki

Youichi Morinaga

Hisashi Takahashi

Tatsuto Oka

Atsushi Yoshimoto

Shunichiro Masaki

Hiroyuki Itokawa

Hiroki Kojima

Yasuhiro Majima

Taketoshi Ochi

A processing circuit includes: a clock generating circuit configured to generate, based on a reference clock signal and a frequency division ratio, a first clock signal; a frequency dividing and delay circuit configured to generate a second clock signal to have a first phase difference with the reference clock signal by dividing the frequency of the first clock signal and delaying the first clock signal based on a phase shift set signal and the frequency division ratio; an analog-to-digital converter circuit configured to convert an analog signal into a digital signal based on the first clock signal and a conversion trigger signal indicating a sampling period and a conversion period; and a control circuit configured to generate the conversion trigger signal to have the same cycle as the second clock signal based on the frequency division ratio and the first clock signal.

Processing circuit, radio communication circuit, and semiconductor integrated circuit

A square detection circuit square-detects a portion of a high frequency transmission signal that is extracted by a directional coupler, of a high frequency transmission signal amplified by a power amplifier. A first adjustment circuit extracts a DC component from a detection output of the square detection circuit, and adjusts respective amplitudes of baseband I and Q signals generated by an I/Q signal generation circuit, in response to the extracted DC component. A second adjustment circuit extracts an AC component from the detection output of the square detection circuit, and adjusts the respective amplitudes and phases, and the respective DC offsets of the baseband I and Q signals generated by the I/Q signal generation circuit, in response to the extracted AC component.

Transmission apparatus

A signal-generating circuit includes a voltage-controlled oscillator that generates an oscillated signal; a first frequency divider that generates a first divided signal by dividing the oscillated signal; a second frequency divider that generates a second divided signal by dividing the divided signal; a phase comparator that receives as input the second divided signal and a reference signal and outputs two signals corresponding to a phase difference therebetween; a loop filter that extracts a low frequency signal between the two signals to be output to the voltage-controlled oscillator; a third frequency divider that generates a third divided signal by dividing the first divided signal; a first frequency converter that generates a first frequency converted signal by multiplying the oscillated signal by the third divided signal; and a first multiplier that generates a multiplied signal by multiplying the first frequency converted signal by a first multiplication number.

Signal-generating circuit and wireless communication device

Provided is a transmission circuit capable of operating with high linearity and with low noise. An AM variable fc filter uses an AM cutoff frequency to remove a high frequency component from an amplitude signal. An amplifier supplies a power amplifier with a voltage which is a result of amplifying the amplitude signal outputted from the AM variable fc filter. A PM variable fc filter uses a PM cutoff frequency to remove a high frequency component from a phase signal. A phase modulator phase-modulates the phase signal outputted from the PM variable fc filter to output a high-frequency phase-modulated signal. The power amplifier amplifies the high-frequency phase-modulated signal by using the voltage supplied from the amplifier, and outputs a resultant signal as a transmission signal. The AM variable fc filter and the PM variable fc filter respectively control the AM cutoff frequency and the PM cutoff frequency such that the AM cutoff frequency and the PM cutoff frequency each have an opposite characteristic to that of an output power of the transmission signal.

Transmission circuit and communication device

A frequency synthesizer () can selectively set an output band of VCO, and consumes less power. The frequency synthesizer () has a frequency converting circuit () that has a mixer () and a frequency divider () connected with each other in parallel. The frequency synthesizer () uses the frequency divider () upon frequency band selection in VCO () and uses the mixer () upon transmission.

Frequency synthesizer and radio transmitting apparatus

Provided are a PLL modulation circuit, a radio transmission device, and a radio communication device capable of maintaining a modulation accuracy for modulation of a wide band. The PLL modulation circuit () includes: a PLL unit (), first modulation signal input means for inputting a first modulation signal to a divider () or a phase comparator () of the PLL unit (); second modulation signal input means for DA converting the digital modulation signal in a DA converter () to generate an analog second modulation signal and inputting it to a voltage control oscillator () of the PLL unit (); a second divider for dividing the output signal of the voltage control oscillator (); and control means for generating a center frequency control signal, a gain control signal, and a second division ration control signal according to the channel selection signal and the control voltage inputted to the voltage control oscillator () and supplying them to the divider (), the DA converter (), and the second divider (), respectively.

PLL modulation circuit, radio transmission device, and radio communication device

Provided is a PLL oscillation circuit that can reduce the variability of modulation sensitivity of a VCOand obtain a desired output amplitude quickly with high precision. An amplitude detectordetects an output amplitude of the VCO. An amplitude controllercontrols a current value of a variable current sourceso as to have an output amplitude of the VCOdetected by the amplitude detectorto be a desired amplitude. A LPFis connected between the amplitude controllerand the variable current source. A switchconnects or disconnects the LPFbetween the amplitude controllerand the variable current source. The amplitude controlleris connected to the variable current sourcethrough either the LPFor the switching switch

PLL oscillation circuit, polar transmitting circuit, and communication device

A two-point modulation type phase apparatus and a wireless communication apparatus capable of achieving a reduction in circuit scale and low power consumption while maintaining modulation precision. It is possible to provide a D/A converter () that converts the inputted digital baseband signal to an analog signal, an adder () that adds an output signal of a D/A converter () and an output of a loop filter () to output to a control voltage terminal of the voltage controlled oscillator (), and a peak control section () provided at a front stage of the D/A converter () that carries out smoothing of peak portions appearing at the inputted digital baseband signal, at a two-point modulation type phase modulation apparatus () that modulates a-carrier frequency signal using an inputted digital baseband signal by setting a frequency dividing ratio of a frequency divider () of a PLL circuit based on an inputted digital baseband modulation signal, and adding a voltage corresponding to a signal that is an inputted digital baseband signal analog-converted for supply to a control voltage terminal of a voltage controlled oscillator ().

Phase modulation apparatus and wireless communication apparatus

The transmission apparatus according to the present invention can reduce transmission output noise leaking into the receiving apparatus even when the transmission apparatus is applied to wireless equipment using the W-CDMA scheme. Transmission apparatus () has bypass circuit () and bypass control circuit () that inputs an RF phase signal to power amplifier () via amplitude adjustment circuit () when bypass circuit () and power amplifier () are operated in non-saturation mode, and that inputs the RF phase signal to power amplifier () via bypass circuit () when power amplifier () is operated in saturation mode.

Transmission apparatus and communication apparatus

A two-point frequency modulation apparatus is proposed whereby the spectrum of transmission waves is kept within the spectrum mask. Voltage is supplied to the control voltage terminal of VCOin accordance with modulation data via noise shaperthat has operating characteristics of attenuating more noise at higher frequencies. As a result, by virtue of the working of noise shaper, the signal level outputted from the PLL circuit combining the modulation signal and the quantization noise decreases in proportion to the distance form the central frequency, so that two-point frequency modulation apparatusis made possible whereby the spectrum of an RF modulation signal is kept within the spectrum mask.

Two-point frequency modulation apparatus

A multimode-based phase modulating apparatus capable of reducing the degradation of modulation precision and suppressing the unnecessary power consumption. This apparatus has a switch for switching the modulation modes of a PLL circuit between a single-point modulation and a double-point modulation. In a case of a narrow modulation bandwidth, the switch is turned off to cease a second digital baseband signal, thereby causing the PLL circuit to perform the single-point modulation in which only a first digital baseband signal from a frequency division rate generating part is used for the modulation. Contrarily, in a case of a wide modulation bandwidth, the switch is turned on, thereby performing the double-point modulation using both the first digital baseband signal and the second digital baseband signal.

Phase modulating apparatus, communication device, mobile wireless unit, and phase modulating method

There provides a two-point modulation phase modulation apparatus capable of obtaining an RF phase modulation signal of superior modulation precision with low power consumption and a simple configuration even in the event of inputting a wide band baseband modulation signal. A differentiator () of the opposite characteristics to the attenuation characteristics of anti-alias filter () is provided at the front stage of a D/A converter (). As a result, it is possible to sufficiently suppress an alias signal without raising the sampling frequency of the D/A converter () (i.e. low power consumption) using an anti-alias filter () of a simple configuration (i.e. low cost) with a low order for a narrower bandwidth than a PLL modulation frequency bandwidth, and it is possible to obtain an RF phase modulation signal where the entire frequency band of input digital baseband modulation signal (S) is reflected in a superior manner.

Two-point modulation type phase modulation apparatus, polar modulation transmission apparatus, wireless transmission apparatus and wireless communication apparatus

A two-point frequency modulation apparatus is provided that reduces input timing difference and improves modulation accuracy. Two-point frequency modulation apparatushas: PLL circuit; frequency division ratio generatorthat generates the frequency division ratio in frequency dividerbased on first digital baseband signal Sand carrier signal; adderthat adds second digital baseband signal Sto the output signal of loop filter; a delay index calculator (filter coefficient calculator) that calculates the delay index based on the magnitude of change in the amplitude of the output signal of adder; and a delay adjuster (digital filter) that shifts the phase of one of first digital baseband signal Sand second digital baseband signal Saccording to the delay index so as to reduce the phase difference.

Two-point frequency modulation apparatus, wireless transmitting apparatus, and wireless receiving apparatus

A broadband modulation PLL includes a PLL portion containing a voltage controlled oscillator (), a frequency divider (), a phase comparator () and a loop filter (). A frequency-dividing ratio of the frequency divider () is controlled to apply modulation, and also an input voltage of the voltage controlled oscillator () is controlled to apply modulation. One of phase modulation data for controlling the frequency dividing ratio and phase modulation data for input voltage of the voltage controlled oscillator () is inverted in phase by using an inverter (), and the delay control circuit () detects a timing error on the basis of a signal () achieved by adding the output signals () and () of the filter () and the loop filter (), and the timing is controlled by the delay circuits () and () to correct, the timing error.

Wide-band modulation PLL, timing error correction system of wide-band modulation PLL, modulation timing error correction method and method for adjusting radio communication apparatus having wide-band modulation PLL

Provided is a transmission modulation apparatus, using polar modulation of two-point modulation scheme, capable of completing a timing adjustment of a BB phase modulation signal and BB amplitude modulation signal in a short time. A phase modulation section () that performs two-point modulation with a PLL circuit is provided with a switch () to make the PLL circuit open loop, and when a first delay section () corrects the deviation in synchronization between the BB phase modulation signal and BB amplitude modulation signal, the switch () is turned off to make the PLL circuit open loop.

Growing community of inventors

Kanagawa, Japan

Shunsuke Hirano