SUPER-WIDEBAND PLANAR-COUPLED SPIRAL BALUN

摘要

PROBLEM TO BE SOLVED: To provide a balun structure which supplies a ballance revers-phase output over the range of super-wideband frequency and whose occupied space is small.;SOLUTION: The coupled trasmitting line balun structure employs two pairs of alternately-positioned spiral coils(3, 5 and 7, 9) which are formed on an electrically insulating or semiinsulating substrate(11) making up the planar structure. One coil of each pair is connected in series to form the input transmitting line of the balun, and one end(8) of the transmitting line is an open circuit. The balun exhibits a super-wideband characteristics in a frequency of MMIC(monolithic microwave integrated circuit) device and is manufactured using the same technology as used in the manufacturing of the MMIC device, and its physical size is suitable to the application to the MMIC device.;COPYRIGHT: (C)2004,JPO