Fujitsu Corporation

Kazuhiro Futamura

Shinsuke Shimahashi

Hideki Watanabe

Radio equipment enabling radio communication with frequency conversion corresponding to signals of different frequency bands is disclosed. A local oscillator signal generator included in this radio equipment having a first signal generator, a second signal generator, and a frequency synthesizer generating a local oscillator signal. A first signal having first frequency is generated in the first signal generator, and a second signal having second frequency smaller than the first frequency is generated in the second signal generator. These first and second signals are synthesized, and the local oscillator signal either having the frequency derived from adding the second frequency to the first frequency, or having the frequency derived from subtracting the second frequency from the first frequency is generated.

Radio equipment communicatable in two frequency bands and method for generating local oscillator signal in radio equipment

A multi-mode communication device includes a receiving unit which receives a radio signal via a radio communication path, and processes the received radio signal, a frequency-component obtaining unit which obtains frequency components in all or part of a frequency range of the received radio signal, and a controlling unit which selects a multiplex-attachment scheme appropriate for the received radio signal from a plurality of applicable multiplex-attachment schemes by controlling said receiving unit, said controlling unit selecting a CDMA scheme as the multiplex-attachment scheme when the frequency components obtained by said frequency-component obtaining unit are substantially uniformly distributed.

Multi-mode communication device

This separating device is provided with a transmitting filter and a receiving filter. Each of the transmitting and receiving filters comprises a variable capacity diode and a resonant element, and compose a band elimination filter. Each of the elimination bands of the transmitting and receiving filters can be adjusted by changing the capacity value of each variable capacity diode. The elimination band of the transmitting filter is adjusted so as to coincide with the receiving frequency of the communication channel currently used. The elimination band of the receiving filter is adjusted so as to coincide with the transmitting frequency of the communication channel currently used.

Growing community of inventors

Kawasaki, Japan

Kazuhiro Futamura