An amplification apparatus as the embodiment of the present invention includes a switching amplifier and an adjuster. The switching amplifier is driven on the basis of a control signal and amplifies an input signal to be amplified to generate an amplified signal. The adjuster adjusts at least one of the signal to be amplified and the control signal before being input into the switching amplifier. In addition, the adjuster adjusts so that timing when the control signal turns from LOW to HIGH aligns with timing when the signal to be amplified turns from LOW to HIGH, or aligns with timing when the signal to be amplified turns from HIGH to LOW.

In a band pass filter, a signal input into a first terminal is transmitted to a first LC resonator and a second LC resonator in this order and is then output from a second terminal. The band pass filter includes a third inductor and a third capacitor. A first end of the third inductor is electrically connected to the ground. The third capacitor is electrically connected between a second end of the third inductor and a node between the first LC resonator and the second LC resonator.

A band-pass filter includes five resonators. The five resonators are configured so that capacitive coupling is established between every two of the resonators adjacent to each other in circuit configuration. The first stage resonator and the fifth stage resonator are magnetically coupled to each other. The second stage resonator and the fourth stage resonator are capacitively coupled to each other. Each of the five resonators includes a resonator conductor portion. The respective resonator conductor portions of the first and fifth stage resonators are physically adjacent to each other. The respective resonator conductor portions of the second and fourth stage resonators are physically adjacent to each other. The respective resonator conductor portions of the first and second stage resonators are physically adjacent to each other. The respective resonator conductor portions of the fourth and fifth stage resonators are physically adjacent to each other.

A band pass filter includes: a first circuit unit including a first series LC resonant circuit disposed between a first terminal and a second terminal; a second circuit unit disposed between the first circuit unit and the second terminal, and including a first parallel LC resonant circuit; and a third circuit unit disposed between the first terminal and a ground, and including a second series LC resonant circuit, wherein a resonant frequency of the first circuit unit is in a pass band.

Methods and system for using a multifunctional filter to minimize insertion loss in a multi-mode communications system are described. Specifically described is a multifunctional filter that is configurable to operate in a band-pass mode when a first type of signal is propagated through the multifunctional filter, and to operate in a low-pass mode when a second type of signal is propagated through the multifunctional filter. The multifunctional filter presents a lower insertion loss to the second type of signal when operating in the low-pass mode than in the band-pass mode.

A deployable active radar countermeasure or smart chaff device includes a flexible battery or length of reflective material for passive reflection of a surveillance radar signal. Metallized antenna elements printed onto the material receive the surveillance radar signals, and RF integrated circuitry bonded to the material generates active RF echo signals based on the frequency of the surveillance signal and the length of the material. Wirebond receiving paths include reconfigurable gain amplifiers and filters for adjusting the phase and amplitude of the echo signal, and transmit paths return the echo signal to the radar source via the antenna elements. Echo signals may combine with those of other such devices, having various lengths and associated frequencies, to simulate a false return associated with a particular aircraft or moving target (e.g., simulation of Doppler shift via offset echo frequencies).

A multilayer band pass filter includes first and second LC parallel resonators. The first and second LC parallel resonators include a first inductor and a second inductor, respectively. The first inductor includes a first line conductive pattern, a first via conductive pattern, and a second via conductive pattern. The first line conductive pattern extends in the X-axis direction on a first dielectric layer. The first via conductive pattern and second via conductive pattern extend from the first line conductive pattern toward a second dielectric layer. The second inductor includes a third via conductive pattern extending in the Z-axis direction.

A vacuum tube and transistor amplifier natural sound field tone dividing system includes: a front-end circuit for receiving and processing an input signal to thereby generate an audio signal; a transistor power amplifying circuit connected to the front-end circuit and adapted to process a low-frequency signal in the audio signal and play the low-frequency signal with a first player; and a vacuum tube power amplifying circuit connected to the front-end circuit and adapted to process a medium-frequency signal and a high-frequency signal in the audio signal, play the medium-frequency signal with a second player, and play the high-frequency signal with a third player, wherein the transistor power amplifying circuit and the vacuum tube power amplifying circuit are independent of each other.

A filter includes two series arm resonators electrically connected in series between two input/output terminals, a parallel arm resonator electrically connected between a ground and a series arm between the two series arm resonators, an inductor electrically connected in parallel to the two series arm resonators, and a matching circuit electrically connected between one of the two series arm resonators and one of the input/output terminals, wherein the two series arm resonators and the parallel arm resonator define a pass band of a bandpass filter, the two series arm resonators and the inductor define an LC resonant circuit, respective anti-resonant frequencies of each of the two series arm resonators and a resonant frequency of the parallel arm resonator are located in a pass band of the LC resonant circuit, and a resonant frequency of the LC resonant circuit is lower than the resonant frequency of the parallel arm resonator.

An antenna switch of a radio frequency module selectively switches at least between connection between a first connection terminal and a common terminal and connection between a second connection terminal and the common terminal. A first connection terminal receives a signal in a first communication band. A second connection terminal receives a signal in a second communication band. When the second connection terminal and the common terminal are in connection with each other, a variable capacitor (C1, C2) of a filter circuit shifts the attenuation band of the filter circuit to a higher band than that when the first connection terminal and the common terminal are in connection with each other.