This paper proposes a new technique to reduce non-linear distortion effects in Orthogonal Frequency Division Multiplexing (OFDM) systems. It exploits virtual carriers, which are modulated by using properly defined 'dummy symbols', to obtain a transmitted signal with reduced envelope variations. With this method no additional redundancy is introduced, thus preserving spectrum efficiency, and no changes at the receiver are required. To evaluate dummy symbols some optimization criteria are investigated; an optimum algorithm and a low complexity iterative algorithm are proposed and compared from the point of view of system performance. The effectiveness of this technique is tested by considering some typical High Power Amplifier (HPA) models and by evaluating performance degradation. A comparisons with other techniques proposed in the literature is also carried out.
Novel low complexity technique to reduce non-linear distortion effects in OFDM systems
TRALLI, Velio;
1998
Abstract
This paper proposes a new technique to reduce non-linear distortion effects in Orthogonal Frequency Division Multiplexing (OFDM) systems. It exploits virtual carriers, which are modulated by using properly defined 'dummy symbols', to obtain a transmitted signal with reduced envelope variations. With this method no additional redundancy is introduced, thus preserving spectrum efficiency, and no changes at the receiver are required. To evaluate dummy symbols some optimization criteria are investigated; an optimum algorithm and a low complexity iterative algorithm are proposed and compared from the point of view of system performance. The effectiveness of this technique is tested by considering some typical High Power Amplifier (HPA) models and by evaluating performance degradation. A comparisons with other techniques proposed in the literature is also carried out.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
