Title :
On the performance of CDMA systems with nonlinear amplifier and AWGN
Author :
Conti, A. ; Dardari, D. ; Tralli, V.
Author_Institution :
Bologna Univ., Italy
Abstract :
This paper proposes and discusses an analytical model for the evaluation of the effects of inband nonlinear distortion on the CDMA system performance. Both synchronous systems with orthogonal codes and asynchronous systems are considered. It is shown that in a broad range of cases, the nonlinear distortion in the decision variables at the receiver can be modeled by means of a complex scale factor and an additive noise, which is uncorrelated to the useful signal. Moreover, an analytical formulation of the bit error probability and total degradation (TD) as a function of output back-off (OBO) and number of user is given and the results are discussed for three classes of HPA models, the traveling wave tube amplifier (TWTA), the solid state power amplifier (SSPA) and the amplifier with ideal predistortion (IPA)
Keywords :
AWGN; code division multiple access; error statistics; microwave power amplifiers; multiuser channels; nonlinear distortion; personal communication networks; power amplifiers; radio receivers; random codes; satellite communication; travelling wave amplifiers; AWGN; CDMA system performance; HPA models; TWTA; additive noise; analytical model; asynchronous systems; bit error probability; capacity degradation; complex scale factor; decision variables; high power amplifier; ideal predistortion amplifier; inband nonlinear distortion; nonlinear amplifier; nonlinear distortion; orthogonal codes; output back-off; personal communications; pseudorandom codes; random codes; receiver; satellite communications; solid state power amplifier; synchronous systems; total degradation; traveling wave tube amplifier; Additive noise; Analytical models; Degradation; Error probability; Multiaccess communication; Nonlinear distortion; Power amplifiers; Solid modeling; Solid state circuits; System performance;
Conference_Titel :
Spread Spectrum Techniques and Applications, 2000 IEEE Sixth International Symposium on
Conference_Location :
Parsippany, NJ
Print_ISBN :
0-7803-6560-7
DOI :
10.1109/ISSSTA.2000.878111
