Lumped-element structures of basic microwave components for large-scale MMIC applications
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Himeji Institute of Technology|
OHTA Isao Faculty of Engineering, Professor, 工学部, 教授 (80047612)
KAWAI Tadashi Faculty of Engineering, Research Associate, 工学部, 助手 (30275309)
|Project Period (FY)
1998 – 1999
Completed(Fiscal Year 1999)
|Budget Amount *help
¥3,500,000 (Direct Cost : ¥3,500,000)
Fiscal Year 1999 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1998 : ¥2,700,000 (Direct Cost : ¥2,700,000)
|Keywords||microwave / microwave passive component / lumped-element component / hybrid / power combiner / divider / multi-port network / マイクロ波回路|
1. Quadrature and 180-degree 3 dB hybrids
(1) The research presents a systematic design concept based on the invariant and the equivalent admittance for lossless reciprocal 4-port circuits with double or single reflection symmetry.
(2) The research derives the frequency characteristics of various hybrids consisting of unbalanced or balanced line LC circuits analytically. Generally, balanced line hybrids exhibit a broader-band property, and the bandwidth of a quadrature hybrid is twice as wide as that of an unbalanced line hybrid. Additionally, a balanced line 180-degree hybrid possesses a wide bandwidth ratio of 3.2. The effect of conductor loss in inductors also is examined.
(3) A new broadband 180-degree hybrid with a phase inverter is proposed. The frequency dependencies are calculated with consideration for the loss of inductors.
(4) An exceedingly miniaturized semi-lumped-element hybrid ring with a considerably broad bandwidth is newly proposed using a phase inverter and shunt capacitors added at each port.
(5) The above hybrids are virtually realized on a GaAs substrate, and the validity of the design technique is demonstrated by an electromagnetic simulator (Sonnet).
(6) Experimental confirmation is shown for a broadened quadrature hybrid.
2. Eight-port hybrids
(1) Various structures are proposed by appropriately connecting four quadrature hybrids, and two typed with a broad bandwidth are elaborated.
(2) A band-broadening technique is described.
3. Wilkinson power divider
(1) The frequency characteristics of a lumped-element construction are derived analytically.
(2) The layout and its frequency properties are shown by and electromagnetic simulator.
4. Future subjects
(1) Development of a new multi-port power divider and N-way Wilkinson power divider.
(2) Investigation on decrease of the conductor loss.
(3) Development of functional devices such as a variable attenuator and a phase shifter.
Research Products (15results)