Abstract: It is an object to obtain a transmission line converter in which a rectangular waveguide provided under a transmission line may be reduced in size. In the transmission line converter including: a rectangular waveguide (11); a slot (5) provided in a wall surface of the rectangular waveguide (11); and a transmission line (13) which extends in a direction of a tube axis of the rectangular waveguide (11) and includes signal conductors (2 and 3) and a ground conductor (4), the slot (5) is provided in a narrower wall surface of the rectangular waveguide (11) and has a shape in which a central portion of the slot (5) includes an oblique portion to the tube axis of the rectangular waveguide (11) and at least one of both end portions of the oblique portion includes a portion parallel to the tube axis of the rectangular waveguide (11), and the wall surface of the rectangular waveguide (11) in which the slot (5) is provided is a part of the ground conductor (4).

Abstract: A transmission line converter in which a rectangular waveguide provided under a transmission line may be reduced in size. The transmission line converter includes: a rectangular waveguide; a slot provided in a wall surface of the rectangular waveguide; and a transmission line which extends in a direction of a tube axis of the rectangular waveguide and includes signal conductors and a ground conductor, the slot is provided in a narrower wall surface of the rectangular waveguide and has a shape in which a central portion of the slot includes an oblique portion to the tube axis of the rectangular waveguide and at least one of both end portions of the oblique portion includes a portion parallel to the tube axis of the rectangular waveguide, and the wall surface of the rectangular waveguide in which the slot is provided is a part of the ground conductor.

Abstract: A bandstop filter where variation in characteristics is suppressed to minimum and which realizes an increased production yield. The physical length of a line joint portion between a main line and an oscillator can be enlarged by providing an impedance non-continuous structure portion in a strip conductor of the oscillator. In comparison to the case where the impedance non-continuous structure portion is not provided, the width of a joint slit required to obtain an equal joint amount can be enlarged. When the joint slit width is enlarged, variation in filter characteristics caused by pattern accuracy can be reduced because of the enlarged joint slip width, thus improving a filter yield. This means that pattern accuracy requirement for production is loosened. Freedom in selecting a dielectric substrate is increased, which also provides an advantage that a filter can be produced using a less expensive dielectric substrate with not very high pattern accuracy.

Abstract: A bandstop filter where variation in characteristics is suppressed to minimum and which realizes an increased production yield. The physical length of a line joint portion between a main line and an oscillator can be enlarged by providing an impedance non-continuous structure portion in a strip conductor of the oscillator. In comparison to the case where the impedance non-continuous structure portion is not provided, the width of a joint slit required to obtain an equal joint amount can be enlarged. When the joint slit width is enlarged, variation in filter characteristics caused by pattern accuracy can be reduced because of the enlarged joint slip width, thus improving a filter yield. This means that pattern accuracy requirement for production is loosened. Freedom in selecting a dielectric substrate is increased, which also provides an advantage that a filter can be produced using a less expensive dielectric substrate with not very high pattern accuracy.

Abstract: The present invention includes: a first main waveguide 1; a T-branch circuit 3 connected thereto; a first low-pass filter 5 connected thereto; a band-pass filter 7 connected to the first T-branch circuit 3; a first converter 8 connected to the first low-pass filter 5 for converting transmission lines between a waveguide and a microwave integrated circuit; an amplifier 10 connected to the first converter and structured by the microwave integrated circuit; a second converter 9 connected thereto for converting transmission lines between a waveguide and the microwave integrated circuit; a second low-pass filter 6 connected thereto; a second T-branch circuit 4 connected to the second low-pass filter and the band-pass filter 7; and a second main waveguide 2 connected to the second T-branch circuit.

Abstract: The present invention includes: a first main waveguide 1; a T-branch circuit 3 connected thereto; a first low-pass filter 5 connected thereto; a band-pass filter 7 connected to the first T-branch circuit 3; a first converter 8 connected to the first low-pass filter 5 for converting transmission lines between a waveguide and a microwave integrated circuit; an amplifier 10 connected to the first converter and structured by the microwave integrated circuit; a second converter 9 connected thereto for converting transmission lines between a waveguide and the microwave integrated circuit; a second low-pass filter 6 connected thereto; a second T-branch circuit 4 connected to the second low-pass filter and the band-pass filter 7; and a second main waveguide 2 connected to the second T-branch circuit.

Abstract: The prior art has a problem in which an isolation between output terminals is deteriorated when a thin film resistor is used as an isolation resistor. Such being the case, in a power divider/combiner comprising an input terminal, two output terminals, two branch lines each connecting the input terminal and one of the output terminals and having a line length that is ¼ of a set wavelength or a multiple of integer of half a wavelength and ¼ of the set wavelength, and an isolation resistor connected to between the output terminals, there is provided an improved power divider/combiner further comprising a transmission line interposed between each of the output terminals and the branch lines. Consequently, even when using the isolation resistor having a length that can not be ignored as compared with a wavelength of a high-frequency signal in use, the isolation between the output terminals can be ensured.

Abstract: An RF circuit module comprising a first RF semiconductor device 19 mounted within a cavity 4 surrounded by a wall 3 of a first dielectric circuit board 1, and a second RF semiconductor device 29 mounted to a second dielectric circuit board 2 placed on the wall 3. A metal base 11 is disposed on the first circuit board 1 and a number of embedded conductors 13 such as via holes are embedded within the wall 3 and arranged to surround the cavity 4 so that each having one end electrically connected to the metal base 11 and the other end exposed and arranged to surround the cavity 4. A metal cover 12 is sealingly attached to the first circuit board 1 to cover the second circuit board 2 and the second RF semiconductor device 29 and electrically connected at the upper surface of the wall 3. Therefore, the first and second RF semiconductor devices are electrically shielded and hermetically sealed, providing an RF circuit module of small-sized and high-performance.

Abstract: A frequency synthesizer, which controls the fluctuation of frequency not only of a long period but also a short period, ensures a wide frequency control range and can be realized at a low cost, can be obtained.