Gsm Dual-band Ltcc Antenna Switch Module Research And Design

The development trend of mobile terminal equipment is miniaturization, portable, integrated, multifunction and low manufacturing cost. People are facing more and more harsh request and a more stern challenge in system research and development (R&D) time, the designed cost and the system integration rate aspect. But the LTCC (Low Temperature Cofired Ceramic) module technology of enhancing the radio frequency (RF) communication electric circuit integration rate becomes the current research hot spot and key.This article studies GSM/DCS the dual range LTCC antenna switch module (ASM) including the research of MMIC (monolithic microwave integrated circuit) single pole double throw switch, the design of LTCC diplexer and filter, and the whole combination about the ASM. The topic affected area is broad, the difficulty is very big and has the challenging extremely.The ASM is composed of two single pole double throw (SPDT) PHEMT absorption switchs and LTCC discreteness (lowpass filter and diplexer). This article first introduced microwave switch's some elementary theories as well as each kind of microwave switch's electric circuit topology, and triumphantly designed a model of SPDT PHEMT absorption switch. Then integrating the project index to elaborate the design way of the LTCC low pass,high pass,band-pass filter and the diplexer, the design file has paid the factory to carry on the production. Finally, by conforming the MMIC SPDT switch and the LTCC diplexer, proposed one kind of design proposal about ASM, and has carried on the three-dimensional model construction and conformity, proved this is a feasible design mentality.The ASM's LTCC discreteness partial size is 4.5mm×3.2mm×1.2mm. At the work frequency range of GSM (824-894MHz) and DCS (1710-1880MHz), the insertion loss are smaller than 1dB. The Attenuation at 2f (f is work frequency rang) and 3f are bigger than 25dB, the VSWR of every port is smaller than 1.7. The performance satisfied the technical specification, and laid down the solid foundation for the ASM's following design.