Renesas Technology Corp.

Ttpcom Limited

Epoch Microelectronics, Inc.

Renesas Electronics Corporation

Ttp Com Limited

Kabushiki Kaisha Toshiba

Hitachi, Ltd.

Ricoh Company, Ltd.

Tipcom Limited

Ttpom Limited

Yasuyuki Kimura

Toshiya Uozumi

Satoshi Tanaka

Robert Astle Henshaw

Hirotaka Oosawa

Ken Suyama

Aleksander Dec

Satoshi Shimizu

Masumi Kasahara

Satoru Yamamoto

Kazuhiko Hikasa

Patrick Wurm

Ryoichi Takano

David Freeborough

Hirotaka Osawa

Masakatsu Yokota

Hiroshi Hagisawa

Robert Astel Henshaw

Masahiko Yamamoto

Satoshi Arayashiki

Hiroaki Matsui

Noriyuki Kurakami

Hirokazu Miyagawa

Akira Okasaka

Yasuo Shima

Yukinori Akamine

Takao Okazaki

Manabu Kawabe

Tomomitsu Kitamura

Masayoshi Ono

Yoshio Ohno

Makiko Watanabe

An internal operation of RF IC is adjusted so that the level of an RF transmitter signal is substantially stopped from rising, or made to descend in course of ramp-up of the RF transmitter signal. This adjustment is enabled by ramp-up adjustment data Last 4 symbols contained in preamble data precedent to real transmission data transmitted after completion of ramp-up. The ramp-up adjustment data and real transmission data are supplied from a baseband LSI. The RF transmitter signal contains phase and amplitude modulation components according to the EDGE system. RF IC includes phase and amplitude modulation control loops PM LP and AM LP. Ramp-up of RF power amplifiers PAand PAis performed by controlling the gain of the first variable amplifier MVGA included in the AM LP according to ramp information. Thus, unwanted radiation's level is reduced during ramp-up of the RF transmitter signal of the RF power amplifiers.

Transmitter, RF transmitter signal processor and method for operation of transmitter

A market-demand-forecasting-value calculation section acquires order entry actual achievement data from an order-entry-actual-achievement-data storing unit of an order receiving system, and calculates a market demand forecasting value using the order entry actual achievement data. A correction safety inventory quantity calculation section calculates an error rate, which becomes negative when an ordering required-quantity becomes large, based on a number of ordered parts and a past ordering required-quantity. Subsequently, the correction safety inventory quantity calculation section calculates a correction safety inventory quantity using the error rate and the market demand forecasting value and a money-amount-zone index value. Further, the correction safety inventory quantity calculation section calculates a determined safety inventory quantity which is a value obtained by adding the correction safety inventory quantity and a reference safety inventory quantity calculated based on the market demand forecasting value.

Inventory management system, inventory management method and computer-readable recording medium

This invention provides a wireless transmitter circuit for mobile communication apparatus and this circuit can be configured with fewer components and is suitable for downsizing. A single PLL synthesizer serves as both RF frequency band PLL and IF frequency band PLL among three oscillators for TX, RX and IF frequency bands, which have been required in conventional mobile communication apparatus. The number of necessary oscillators occupying a large area within a chip is reduced and the number of components is decreased. Specifically, circuitry is arranged to generate local oscillation signals for RF and IF frequency bands by frequency dividing the output of a VCO of the RF frequency band PLL.

Wireless transmitter circuit and transceiver using the same

A semiconductor integrated circuit having a built-in PLL circuit which has two charge pump circuits for charging and discharging capacitive elements of a loop filter in response to signals generated by a phase comparator circuit. One of the two charge pump circuits has current sources which generate current values smaller than those generated by current sources of the other charge pump circuit. The loop filter has a first capacitive element connected to a charge/discharge node, and a second capacitive element connected to the charge/discharge node through a resistive element. The first capacitive element is charged and discharged by the one charge pump circuit, while the second capacitive element is charged and discharged by the other charge pump circuit. A charging current source of the one charge pump circuit operates simultaneously with a discharging current source of the other charge pump circuit, i.e., the charge pump circuits operate in opposite phase.

Semiconductor integrated circuit having built-in PLL circuit

In a communication semiconductor integrated circuit device using offset PLL architectures and including an oscillator circuit and a frequency divider circuit generating an intermediate frequency signal, the oscillator circuit includes an oscillator, a programmable frequency divider which frequency-divides the oscillation signal in accordance with frequency division information, a phase comparator detecting a phase difference between an output signal of the programmable frequency divider and a reference signal, and a frequency control unit for outputting a signal indicative of the phase difference and controlling the oscillation frequency of the oscillator, wherein a frequency division ratio generator circuit generates an integer part I and a fraction part F/G based on band information concerning the use frequency band and mode information along with channel information and for producing the frequency division ratio information to thereby give it to the programmable frequency divider.

Communication semiconductor integrated circuit device and a wireless communication system

The invention provides a communication semiconductor integrated circuit (RF IC) that, when a transmission oscillator is incorporated into a semiconductor chip, secures the oscillation operation over a wide frequency range, prevents a deterioration of a transmission spectrum, and thereby enhances the accuracy of an oscillation frequency. The integrated circuit corrects a dispersion of the KV characteristic of the transmission oscillator by calibrating a current Icp of the charge pump inside the phase control loop. More in concrete, the integrated circuit measures a KV value Kv of the transmission oscillator, and calibrates the current Icp of the charge pump so that Kv&#xb7;Icp falls into a predetermined value.

Communication semiconductor integrated circuit device for use in a mobile communication device for correcting variations in the oscillation frequency of a transmission oscillator by calibrating a current of the charge pump

A transmitter adopting a polar loop system including a phase control loop for controlling the phase of a carrier signal outputted from a transmitting oscillator and an amplitude control loop for controlling the amplitude of a transmitting output signal outputted from a power amplification circuit, and designed to be capable of performing transmission using a GMSK modulation mode and transmission using an 8-PSK modulation mode. In the transmitter, the phase control loop is shared as a phase control loop for use in the GMSK modulation mode and a phase control loop for use in the 8-PSK modulation mode. A component similar to any one of components constituting a loop filter is provided in parallel therewith so that the component can be connected or disconnected in accordance with the modulation mode, for example, by use of a switching element.

Transmitter and semiconductor integrated circuit for communication

A semiconductor integrated circuit device for communication is provided with a PLL circuit or the like formed therein, the PLL circuit which is capable of realizing the compensation of fluctuation due to temperature change, the inhibition of increase in the chip area and the ensurement of the performance margin, and which controls a VCO having multiple oscillation frequency bands. In the case where automatic calibration is performed by switching a switch to a side of a DC voltage source in the PLL circuit using a VCO having multiple oscillation bands, a tuning voltage (Vtune) of an RFVCO is fixed to a voltage value of a DC voltage source. However, since a temperature characteristic of canceling a VCO oscillation frequency is given to the DC voltage source, it is possible to minimize the influence on the band selection when a calibration table comes to no optimum one.

PLL circuit having a multi-band oscillator and compensating oscillation frequency

Wireless communication apparatus having a phase control loop shared by first and second modulation modes and an amplitude control loop

Calibrated PLL for wide band communication semiconductor integrated polar loop transmitter

Growing community of inventors

Maebashi, Japan

Yasuyuki Kimura