Joint Impact of Frequency Synchronization Errors and Intermodulation Distortion on the Performance of Multicarrier DS-CDMA Systems

• Main Authors: Rugini Luca, Banelli Paolo
• Format: Article
• Language: English
• Published: SpringerOpen 2005-01-01
• Series: EURASIP Journal on Advances in Signal Processing
• Subjects: multicarrier DS-CDMA; carrier frequency offset; intermodulation distortion; Rayleigh fading
• Online Access: http://dx.doi.org/10.1155/ASP.2005.730

<p/> <p>The performance of multicarrier systems is highly impaired by intercarrier interference (ICI) due to frequency synchronization errors at the receiver and by intermodulation distortion (IMD) introduced by a nonlinear amplifier (NLA) at the transmitter. In this paper, we evaluate the bit-error rate (BER) of multicarrier direct-sequence code-division multiple-access (MC-DS-CDMA) downlink systems subject to these impairments in frequency-selective Rayleigh fading channels, assuming quadrature amplitude modulation (QAM). The analytical findings allow to establish the sensitivity of MC-DS-CDMA systems to carrier frequency offset (CFO) and NLA distortions, to identify the maximum CFO that is tolerable at the receiver side in different scenarios, and to find out the optimum value of the NLA output power backoff for a given CFO. Simulation results show that the approximated analysis is quite accurate in several conditions.</p>