Nippon Telegraph and Telephone Corporation

Yo Yamaguchi

Kazuhiro Uehara

Hideyuki Nosaka

Hiroyuki Shiba

Kazunori Akabane

Doohwan Lee

Akihiro Yamagishi

Kenjiro Nishikawa

Takayuki Yamada

Takana Kaho

Munenari Kawashima

Akira Minakawa

A receiver includes a local signal generator, a power phase adjuster, and a frequency converter so as to perform frequency conversion on signals included in a plurality of radio frequency bands. The local signal generator supplies a plurality of local signals. The power phase adjuster adjusts local signals in terms of signal power or relative phases. The frequency converter performs frequency conversion on radio frequency bands by use of local signals adjusted with the power phase adjuster, thus sorting them in a desired frequency range.

Receiver

A wideband low-noise amplifier of the present invention is designed such that an input terminal is connected to a base of a first transistor, one terminal of a first passive element, and one terminal of a third passive element; an emitter of the first transistor is grounded; a collector of the first transistor is connected to an output terminal, a base of a second transistor, one terminal of a capacitor, and one terminal of a second passive element; the other terminal of the first passive element is connected to the other terminal of the capacitor; an emitter of the second transistor is connected to the other terminal of the third passive element; and a power terminal is connected to a collector of the second transistor and the other terminal of the second passive element, wherein impedance of the third passive element is determined based on impedance of the first transistor whose emitter size is determined to suite desired saturation level of amplification, thus establishing input impedance matching.

Wideband low-noise amplifier

A programmable delay generator comprises a first ramp wave generator and a second ramp wave generator, each having the same structure as each other, each of them operating with external common clock pulses, and each of them providing potential gradient and final potential incorporated with an external set data; a comparator for comparing an output (V,) of the first ramp wave generator and an output (V,) of the second ramp wave generator so that an output pulse is provided when the outputs of two ramp wave generators coincide with each other; said first ramp wave generator providing a first ramp voltage (V,) upon receipt of a first set data (S) at a predetermined time (t,); said second ramp wave generator providing a threshold voltage (V,) upon receipt of a second set data (K) at a time which preceds at least one clock time (T) than said predetermined time (t,); said comparator providing an output pulse delayed by delay time (t,) which is proportional to ratio (K/S) of said second set data (K) and said first set data (S) from said predetermined time. An application circuit using said programmable delay generator, including a frequency synthesizer, a frequency multiplier, a duty ratio converter, and a PLL frequency synthesizer is also provided.

Programmable delay generator and application circuits having said delay generator

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Yokosuka, Japan

Yo Yamaguchi