Title :
A novel surface-mount RF delay filter for feedforward LPAs
Author :
Cantrell, William H. ; Anderson, Dale R. ; Meszko, William R.
Author_Institution :
Motorola R&D Center, Fort Worth, TX, USA
Abstract :
A novel time-delay filter design is presented that uses a cascade of surface-mount coaxial ceramic delay lines. Quarter-wave microstrip lines are used as impedance inverters to extend the operating bandwidth of the ceramic delay lines. Ideally, no tuning is involved. A theoretical analysis is presented. Two different high-power low-loss delay filters are simulated, built and tested for the 869-894 MHz cellular band. Performance limitations due to circuit parasitics are discussed.
Keywords :
UHF power amplifiers; ceramics; delay filters; delay lines; feedforward; impedance convertors; microstrip lines; 869 to 894 MHz; coaxial resonator; feedforward linear power amplifiers; impedance inverter; power amplifier; quarter-wave microstrip line; surface-mount RF delay filter; surface-mount coaxial ceramic delay lines; time-delay filter; Bandwidth; Ceramics; Circuit optimization; Coaxial components; Delay lines; Filters; Inverters; Microstrip; Radio frequency; Surface impedance;
Conference_Titel :
Microwave Symposium Digest, 2005 IEEE MTT-S International
Print_ISBN :
0-7803-8845-3
DOI :
10.1109/MWSYM.2005.1517116
