Abstract: To provide a millimeter waveband filter which can vary a resonance frequency in a wider band without causing deterioration of resonance characteristics due to leakage of electromagnetic waves. In a millimeter waveband filter 20, a first waveguides 22 and a second waveguide 24 are relatively moved to vary the interval between the electric wave half mirrors 30A and 30B, and the resonance frequency of a resonator formed between the mirrors varies to selectively transmit resonance frequency components. A groove 60 which has a length p along a longitudinal direction of the transmission line corresponding to a ¼ wavelength of electromagnetic waves to be a leakage prevention target is provided on the outside of the second waveguide 24 facing the inside of the first waveguide 22, thereby preventing leakage of electromagnetic waves from the gap between the first waveguide 22 and the second waveguide 24.

Abstract: In a millimeter waveband filter, electric wave half mirrors are provided in transmission lines of a first waveguide configured to allow electromagnetic waves in a predetermined frequency range of a millimeter waveband to propagate in a TE10 mode and a second waveguide connected to the first waveguide in a state where one end of the second waveguide is inserted into the first waveguide, and the waveguides are relatively moved to vary the interval between the electric wave half mirrors, thereby changing a resonance frequency. The first waveguide is a square waveguide, and the second waveguide is a ridge waveguide in which the outside thereof is a rectangular shape at a predetermined interval with respect to the inside of the first waveguide and a sectional shape of a transmission line has a central portion having a height smaller than both side portions.

Abstract: To provide a millimeter waveband filter which can vary a resonance frequency in a wider band without causing deterioration of resonance characteristics due to leakage of electromagnetic waves. In a millimeter waveband filter 20, a first waveguides 22 and a second waveguide 24 are relatively moved to vary the interval between the electric wave half mirrors 30A and 30B, and the resonance frequency of a resonator formed between the mirrors varies to selectively transmit resonance frequency components. A groove 60 which has a length p along a longitudinal direction of the transmission line corresponding to a ¼ wavelength of electromagnetic waves to be a leakage prevention target is provided on the outside of the second waveguide 24 facing the inside of the first waveguide 22, thereby preventing leakage of electromagnetic waves from the gap between the first waveguide 22 and the second waveguide 24.

Abstract: In a millimeter waveband filter, electric wave half mirrors are provided in transmission lines of a first waveguide configured to allow electromagnetic waves in a predetermined frequency range of a millimeter waveband to propagate in a TE10 mode and a second waveguide connected to the first waveguide in a state where one end of the second waveguide is inserted into the first waveguide, and the waveguides are relatively moved to vary the interval between the electric wave half mirrors, thereby changing a resonance frequency. The first waveguide is a square waveguide, and the second waveguide is a ridge waveguide in which the outside thereof is a rectangular shape at a predetermined interval with respect to the inside of the first waveguide and a sectional shape of a transmission line has a central portion having a height smaller than both side portions.

Abstract: In a random error signal generator, an M-sequence generation circuit outputs, in parallel, pieces of bit data stored in each register, a first generation circuit sequentially outputs first reference values C which are changed by a predetermined value in response to clocks, a second generation circuit outputs a second reference value D which is shifted from the first reference value C by a range value E which is determined depending on an error rate p. A comparison and determination unit outputs random error signals to be error bits when a numeric value A of the bit data output exists between the first and second reference values C, D. The random error signal has the error rate p, the number of times of error occurrences follows Poisson distribution, and a distribution of adjacent error occurrence intervals follows a geometric distribution.

Abstract: In a random error signal generator, an M-sequence generation circuit outputs, in parallel, pieces of bit data stored in each register, a first generation circuit sequentially outputs first reference values C which are changed by a predetermined value in response to clocks, a second generation circuit outputs a second reference value D which is shifted from the first reference value C by a range value E which is determined depending on an error rate p. A comparison and determination unit outputs random error signals to be error bits when a numeric value A of the bit data output exists between the first and second reference values C, D. The random error signal has the error rate p, the number of times of error occurrences follows Poisson distribution, and a distribution of adjacent error occurrence intervals follows a geometric distribution.