Renesas Technology Corp.

Ttpcom Limited

Renesas Electronics Corporation

Tipcom Limited

Toyohiko Hongo

Satoshi Tanaka

Taizo Yamawaki

Kazuo Watanabe

Masumi Kasahara

Kumiko Takikawa

Masao Hotta

Toshinori Hirashima

A transceiver suitable for larger scale of integration employs direct conversion reception for reducing the number of filters. Also, the number of VCOs is reduced by utilizing dividers to supply a receiver and a transmitter with locally oscillated signals at an RF band. Dividers each having a fixed division ratio are used for generating locally oscillated signals for the receiver, while a divider having a switchable division ratio are used for generating the locally oscillated signal for the transmitter. In addition, a variable gain amplifier for baseband signal is provided with a DC offset voltage detector and a DC offset canceling circuit for supporting high speed data communications to accomplish fast cancellation of a DC offset by eliminating intervention of a filter within a feedback loop for offset cancellation.

Mobile communication apparatus

A radio transmitting/receiving device having at least three modules. The first module includes a first function for amplifying a radio frequency signal, demodulating the amplified radio frequency signal to a baseband signal and outputting the same, and a second function for modulating the input baseband signal, converting the modulated baseband signal to a radio frequency and outputting the same. The second module includes a function for amplifying the input radio frequency. The third module includes a function for executing a baseband signal process and controlling respective units according to a transmission/reception sequence based on a communication protocol.

Radio transmitting/receiving device

Mobile communication apparatus including dividers in transmitter and receiver

Growing community of inventors

Musashimurayama, Japan

Toyohiko Hongo