Fujitsu Ten Limited

Toyota Jidosha Kabushiki Kaisha

Kazuo Takayama

Kazushige Ogino

Keita Taniguchi

Hirokazu Matsunaga

Kohta Miyagi

Kiyoshi Taniyoshi

Toshihiko Kondo

Hiroshi Iijima

Susumu Hasegawa

Ryokichi Doi

Naoki Kushima

Yoshio Umezawa

Hidefumi Fuse

Kenji Kawai

Kouichi Chikaishi

Kohichi Tsutsui

Mansaku Nakano

Katsuhiro Tsuruta

Eri Miyoshi

Koji Nagao

Tetsuharu Imoto

Nobuyoshi Tateishi

Shuji Sugahara

Kohzoh Nishiwaki

To provide a broadcast receiving apparatus including an AM detector, an AM noise detector, an FM detector, an FM noise detector and a noise determining unit. The AM detector performs AM detection on an IF signal in airwaves received by a receiving antenna that receives incoming airwaves to acquire an AM detection signal. The AM noise detector detects noise components in the AM detection signal. The FM detector performs FM detection on the IF signal to acquire an FM detection signal. The FM noise detector detects noise components in the FM detection signal. The noise determining unit determines a noise status of a broadcast signal based on detection results acquired by the AM noise detector and the FM noise detector.

Broadcast receiving apparatus and method of determining presence of noise performed by broadcast receiving apparatus

To provide a broadcast receiving apparatus including an AM detector, an AM noise detector, an FM detector, an FM noise-level detector, and a threshold control unit. The AM detector performs AM detection on a broadcast signal in airwaves received by a receiving antenna that receives incoming airwaves to acquire an AM detection signal. The AM noise detector detects a signal portion, in which the AM detection signal exceeds an AM noise threshold, as an AM noise component. The FM detector performs FM detection on the broadcast signal to acquire an FM detection signal. The FM noise-level detector detects an FM noise level of the FM detection signal. When the FM noise-level detector detects the FM noise level of the FM detection signal, the threshold control unit changes setting of the AM noise threshold in the AM noise detector based on the FM noise level of the FM detection signal.

Broadcast receiving apparatus and method of detecting noise components performed by broadcast receiving apparatus

An antenna device that is placed adjacent to an antennafor receiving a high frequency signal and includes an impedance matching circuitand an amplifying circuitto which a DC control voltage is supplied from a demodulating devicethrough a feeder cablefor transmitting the high frequency signal to the demodulating device, wherein the DC control voltage is set to a value for adjusting a frequency characteristic of the impedance matching circuitwithin an allowable range corresponding to a received frequency. A small and inexpensive antenna device having a simple circuit configuration and good reception sensitivity is implemented.

Antenna device, demodulating device and receiving device

A heating line pattern structure is provided, in which the effect of the heating lines of a defogger on an antenna for a TV broadcast especially for a digital TV broadcast may be decreased. The defogger is structured by arranging heating lines between bus bars on both sides. The portion of an uppermost heating line in proximity to the monopole antenna are folded rectangularly at a regular interval to form a meander shape. One lateral heating line is extended under the meander-shaped heating line portion, and is connected to a vertical heating line to which four lateral heating lines are connected together.

Heating line pattern structure of defogger formed on rear window glass panel of motor vehicle and rear glass panel

When configuring a film antenna for receiving a circular polarized wave, at least one loop antenna is formed on a transparent plastic film and, at the same time, a non-powered element constituted by a wire-shaped conductor independent from the antenna conductor configuring the loop is arranged near this loop antenna. The non-powered element arranged on the side of the loop antenna is configured by a first part and a second part. The first part is made close to the loop antenna in a substantially parallel state. When a monopole antenna is used in place of the loop antenna, by combining this with a wire-shaped conductor orthogonal to this, it becomes possible to receive a circular polarized wave by a configuration providing a power transfer part between the two. It is also possible to configure a composite antenna by mounting another antenna on the transparent plastic film. This antenna can be used as an antenna of a navigation system.

Circular polarization antenna and composite antenna including this antenna

An object of the invention is to receive a weak signal with high sensitivity and reduce distortion and signal suppression when a strong interference signal exists. When a high-frequency signal received by an antenna is to be amplified by an antenna amplifier and when an interference wave of high field strength exists, a switch circuit is switched by an output switchover circuit from the output of an amplifier to a through-circuit. The through-circuit guides the high-frequency signal, directly to the output side without passing through the amplifier. When the switching operation of the switch circuit is performed based on low-frequency components which are highly correlated with distortion components due to intermodulation, the switching operation can be performed more adequately. Noises can be reduced by performing a smoothing process on the switching operation, and the use of an inverting amplifier can prevent occurrence of oscillation.

Antenna amplifier and shared antenna amplifier

An audio broadcast receiving apparatus and an audio broadcast receiving method implemented by the audio broadcast receiving apparatus are disclosed. A tuner simultaneously receives a radio wave in a specific frequency band of the analog audio broadcast and a radio wave of the digital audio broadcast transmitted in parallel with the analog audio broadcast in the specific frequency band. A demodulator retrieves the intended audio information by demodulating the signal received by the tuner. An analog receiving signal bandpass filter selectively passes the receiving signal corresponding to the analog audio broadcast radio wave. An analog receiving signal amplifier outputs an output signal representing an amplified receiving signal that has passed the analog receiving signal bandpass filter to the demodulator, and the gain of the amplifier is controlled in accordance with the level of the same output signal. A digital receiving signal bandpass filter selectively passes the receiving signal corresponding to the digital audio broadcast radio wave. A digital receiving signal amplifier amplifies the receiving signal that has passed through the digital receiving signal bandpass filter with a gain controlled in accordance with the level of the same output signal and outputs the amplified signal to the demodulator.

Audio broadcast receiving apparatus and method

Pulse noise detecting circuit of AM receiver

A branching filter, which is operatively connected between an antenna and a communication device which utilizes different frequency bands, suppresses a mutual interference between signals transmitted to and from the communication device. An antenna circuit, which is operatively connected between the antenna, or a branching filter, and the communication device, converts an impedance with respect to a signal in a frequency band having a lower frequency, and reduces loss resulting from a capacitive antenna impedance.

Antenna circuit for a multi-band antenna

An antenna element including a loading coil is telescopically extendable and retractable from within a housing tube. A characteristic impedance of a transmission line from a lower end part of the antenna element to a cable is equal to one of a cable. A part of the loading coil is reinforced. A branching filter, which is operatively connected between the antenna and a communication device using a different frequency band, suppresses a mutual interference between signals for the communication device. An antenna circuit, which is operatively connected between the antenna or a branching filter and the communication device, converts an impedance of a lower part in a frequency band, and reduces a loss due to a capacitive antenna impedance.

Mobile telescoping whip antenna with impedance matched feed sections

Disclosed is a mobile radio-receiver system built-into an FM radio-receiver set installed in a vehicle, wherein a reproduction characteristic of a reception signal, such as a sound signal, having noise superimposed thereon is improved. The mobile radio-receiver system includes a space diversity unit which receives two reception signals and selects one reception signal on which noise is smaller than on the other reception signal, and a signal prediction unit which ignores the selected signal for a predetermined time in which large noise remains in the selected signal, and predicts a reception signal for the ignored selected signal for the predetermined time, so that a quality of a reproduction sound from the FM radio-receiver set is greatly improved.

Mobile radio-receiver system with improved reproduction characteristics

A noise reduction apparatus in which an input signal is supplied to a first signal path (2) including a variable low-pass filter (2) and a second signal path (1), a control circuit (4) control is such that a cut-off frequency of the variable low-pass filter (2) is varied in accordance with a frequency of the input signal S(1), and an output signal is obtained from the first signal path when noise is generated and from the second signal path when noise is not generated.

Noise reduction apparatus

A high frequency amplifier circuit includes a series resonance circuit resonating at a desired frequency, first transistor to the gate of which are applied signals and to the source of which is connected the series resonance circuit, a second transistor to the base of which is applied the output signal from the first transistor, and third and fourth transistors having their emitters connected to the second transistor. The collector of the third transistor is connected to the source of the first transistor. A parallel resonance circuit resonates at the desired frequency. The collector of the fourth transistor is connected to the source of the first transistor via the parallel resonance circuit. An AGC circuit applies AGC voltage to the bases of the third and fourth transistors for the purpose of varying the collector current ratio of both the transistors. Negative feedback is accomplished in the circuit, and output power is obtained from the parallel resonance circuit.

High frequency amplifier circuit

Intermediate frequency detection circuit

An antenna input circuit for an electronic tuning type AM receiver for automobiles, which is connected to a capacitive antenna represented by an equivalent circuit composed of an antenna capacitance connected in series with an antenna electromotive force and a cable capacitance connected in parallel with them. A tuning transformer and a variable capacitance diode are connected in series with the capacitive antenna, and an additional capacitance is connected to the tuning transformer so that the current flowing in the additional capacitance also flows in one part of the tuning transformer, thereby providing an improved S/N ratio in the medium-frequency receiving band. Another capacitance is connected to the output terminal of the antenna input circuit, to reduce its output impedance. A capacitance for image interference ratio improving use is connected to the additional capacitance and the output impedance reducing capacitance.

Growing community of inventors

Kobe, Japan

Kazuo Takayama