Abstract: An integrated circuit including a distributed amplifier is disclosed. The integrated circuit includes a plurality of amplification stages, each stage connected to an input signal and an output signal. At least one amplification stage includes an amplification transistor such as a field effect transistor (FET) having a gate, a source, and a drain, the gate connected to the input signal and a feedback path between the drain and the gate. The feedback path is implemented with another FET having a gate, a source, and a drain; its gate is connected to a control signal; its drain is connected to the drain of the amplification FET; and its source is connected to the gate of the amplification FET. The feedback path provides variable resistive feedback and allows the amplification FET to operate at its linear response portion of its characteristic curve even when its gain is controlled by a control signal.

Abstract: Monolithic transformer based amplifier for integrated circuits. The amplifier includes an input transformer with a first impedance transforming ratio. The input transformer includes a coupled line structure. An amplification circuit is coupled to the input transformer. The amplifier also includes an output transformer with a second impedance transforming ratio that is coupled to the amplification circuit.

Abstract: An image rejection mixer including a first and a second hybrid couplers and a first and a second traveling-wave mixers is disclosed. The first hybrid coupler divides an input radio frequency (RF) signal to a first RF signal and a second RF signal, the second RF signal being in quadrature to the first RF signal. The first traveling-wave mixer mixes the first RF signal and a local oscillator (LO) signal to produces a first intermediate frequency (IF) signal. The second traveling-wave mixer mixes the second RF signal and the local oscillator signal to produces a second IF signal. The second hybrid coupler combines the first IF signal and the second IF signal to produce an upper sideband of the IF signals and a lower sideband of the IF signals. The use of the traveling-wave mixers allow for a wide bandwidth operation of the image rejection mixer.

Abstract: An up-conversion mixer includes a first and a second hybrid couplers and a first and a second traveling-wave mixers is disclosed. The first hybrid coupler receives an input intermediate frequency (IF) signal and produces a first IF signal (IF1) and a second IF (IF2) signal, the second IF signal being 180 degree off-phase compared to the first IF signal. The first traveling-wave mixer mixes the first IF signal (IF1) and a first local oscillator (LO1) signal to produces a first radio frequency signal (RF1). The second traveling-wave mixer mixes the second IF signal (IF2) and a second local oscillator signal (LO2) to produces a second RF signal (RF2). The second hybrid coupler to combines the first RF signal and the second RF signal to produce an output RF signal. The use of the traveling-wave mixers allow for a wide bandwidth operation of the up-conversion mixer.

Abstract: A mobile radiotelephone connecting apparatus and system by which mobile type telephone conversation can be realized using a network is disclosed. A plurality of groups each including a mobile radiotelephone set, a mobile radiotelephone connecting apparatus and a personal computer are connected to one another through a LAN. The mobile radio telephone connecting apparatus includes a Bluetooth interface for performing low-power radio communication, a LAN interface for establishing a connection to the LAN, a USB interface for establishing connection to the personal computer, and a CPU interposed among the mobile ratio telephone set, LAN and personal computer for allowing communication among the three.

Abstract: A relay apparatus includes an external connection interface section and common terminal section. A plurality of communication sections are connected to the external connection interface section. The external connection interface section individually interfaces with the communication sections. The common terminal section is commonly provided for the communication sections and controls to perform communication by using one of the communication sections connected to the external connection interface section in accordance with operation by a user.

Abstract: A mobile radiotelephone connecting apparatus and system by which mobile type telephone conversation can be realized using a network is disclosed. A plurality of groups each including a mobile radiotelephone set, a mobile radiotelephone connecting apparatus and a personal computer are connected to one another through a LAN. The mobile radio telephone connecting apparatus includes a Bluetooth interface for performing low-power radio communication, a LAN interface for establishing a connection to the LAN, a USB interface for establishing connection to the personal computer, and a CPU interposed among the mobile ratio telephone set, LAN and personal computer for allowing communication among the three.