Title :
Transmitter utilising bandpass delta-sigma modulator and switching mode power amplifier
Author :
Ketola, Jaakko ; Sommarek, Johan ; Vankka, Jouko ; Halonen, Kari
Author_Institution :
Electron. Circuit Design Lab., Helsinki Univ. of Technol., Finland
Abstract :
In this paper a concept of a transmitter using delta-sigma modulation and switching mode power amplifier is presented. The specifications of a WCDMA base station transmitter are as an objective. Using a delta-sigma modulation in a D/A conversion, most of the nonlinearities of a multi-bit D/A converter are avoided. In addition the 1-bit output signal of the delta-sigma modulator is suitable for power efficient switching mode power amplifiers. The use of the images of the signal is studied as a method to reduce the required sampling frequency. The problems and possible solutions in implementing a wideband transmitter with this topology are discussed as well.
Keywords :
code division multiple access; control nonlinearities; delta-sigma modulation; integrated circuit design; modulators; power amplifiers; radio transmitters; switching circuits; D-A conversion; D-A converter nonlinearities; WCDMA base station transmitter; bandpass delta-sigma modulator; delta-sigma modulation; multibit D-A converter; power efficiency; required sampling frequency reduction; signal images; switching mode power amplifier; wideband transmitter implementation; Base stations; Broadband amplifiers; Delta modulation; Delta-sigma modulation; Frequency; Image converters; Image sampling; Multiaccess communication; Power amplifiers; Transmitters;
Conference_Titel :
Circuits and Systems, 2004. ISCAS '04. Proceedings of the 2004 International Symposium on
Print_ISBN :
0-7803-8251-X
DOI :
10.1109/ISCAS.2004.1328274
