Title :
Dual-band transmitters using digitally predistorted frequency multipliers for software defined radios
Author :
Park, Youngcheol ; Melville, Robert ; Frye, Robert C. ; Chen, Min ; Kenney, J. Stevenson
Author_Institution :
Georgia Inst. of Technol., Atlanta, GA, USA
Abstract :
Two methods of implementing dual-band transmitters using re-configurable circuits operating in conjunction with digital predistortion linearizers are investigated. One method utilizes a circuit topology that can be switched between a fundamental-mode in-phase combined amplifier, and a push-push frequency doubler. Measurement results indicated that the circuit was able to amplify IS-95 B CDMA signals in either the 881 MHz, or the 1763 MHz band with an adjacent-channel power ratio (ACPR) of -48 dBc/30 kHz. Another method that was investigated utilizes fundamental-frequency power amplifier followed by a varactor multiplier that can be bypassed. A varactor-diode doubler with a conversion loss of 3.3 dB was built and tested. An ACPR of -53 dBc/30 kHz at 885 kHz offset was achieved for a CDMA signal transmitted at 1892 MHz.
Keywords :
code division multiple access; frequency multipliers; network topology; power amplifiers; radio transmitters; varactors; 1763 MHz; 1892 MHz; 3.3 dB; 881 MHz; 885 kHz; CDMA signals; adjacent channel power ratio; circuit topology; code division multiple access; conversion loss; digital predistortion linearizers; digitally predistorted frequency multipliers; dual band transmitters; frequency power amplifier; push-push frequency doubler; software defined radios; varactor diode doubler; varactor multiplier; Circuit topology; Dual band; Frequency; Multiaccess communication; Predistortion; Radio transmitters; Radiofrequency amplifiers; Radiofrequency integrated circuits; Software radio; Switching circuits;
Conference_Titel :
Microwave Symposium Digest, 2004 IEEE MTT-S International
Print_ISBN :
0-7803-8331-1
DOI :
10.1109/MWSYM.2004.1336038
