Title :
Reducing the crest factor of CDMA downlink signal by adding unused channelization codes
Author :
Väänänen, Olli ; Vankka, Juoko ; Viero, Timo ; Halonen, Kari
Author_Institution :
Electron. Circuit Design Lab., Helsinki Univ. of Technol., Espoo, Finland
Abstract :
In a CDMA system the downlink signal typically has a high peak to average ratio, (crest factor). This sets strict requirements for the linearity of the power amplifier, which leads to poor efficiency and high costs. This paper discusses a method for reducing the crest factor based on the addition of a signal which is orthogonal to all the active channel codes. Therefore, in ideal case, no error is introduced at the receiver.
Keywords :
channel coding; code division multiple access; mobile radio; modulation; radio receivers; spread spectrum communication; CDMA downlink signal; active channel codes; crest factor reduction; orthogonal signal; peak to average ratio; receiver; unused channelization codes; Baseband; Downlink; Electronic circuits; Laboratories; Linearity; Multiaccess communication; OFDM; Peak to average power ratio; Signal design; Signal generators;
Conference_Titel :
Spread Spectrum Techniques and Applications, 2002 IEEE Seventh International Symposium on
Print_ISBN :
0-7803-7627-7
DOI :
10.1109/ISSSTA.2002.1048583