36 research outputs found
Power-efficient distributed resource allocation under goodput QoS constraints for heterogeneous networks
Performance Analysis of a MC-CDMA Forward Link over Nonlinear Channels
This paper presents an analytical framework for the performance evaluation of an MC-CDMA forward-link in the presence of nonlinear distortions induced by transmitter's high-power amplifiers. The statistical characterization of the decision variable used for data detection is carried out through the application of the Bussgang theorem. Simulation results validate the accuracy of the proposed method under typical operating conditions
Iterative Nonlinear Channel Compensation for MC-CDMA Satellite Transmissions
In this paper we illustrate an efficient iterative multi-user predistorter scheme for the down-link of a satellite multiple access MC-CDMA which mitigates the nonlinear distortions induced by the power amplifier. Simulation results demonstrate that the proposed scheme can significantly improve the power efficiency of the satellite link
Theoretical Characterization of Nonlinear Distortion Noise in MC-CDMA Transmissions
This paper presents an analytical framework for the theoretical characterization and performance evaluation of an MC-CDMA forward-link in the presence of nonlinear distortions induced by transmitter's high-power amplifiers. The analytical characterization of the signal features, both in the time and frequency domains, is carried out through the application of the Bussgang theorem. Simulation results are derived to validate the accuracy of the proposed method under typical operating conditions
Minimum-PAPR Waveform Design for MC-CDMA Transmissions over Nonlinear Channels
In this contribution we demonstrate that the peak-to-average power ratio (PAPR) of a Multi-Carrier Code Division Multiple Access (MC-CDMA) signal can be suitably minimized by resorting to a judicious strategy for the allocation of the spreading signature codes. A low-complexity implementation of the proposed strategy is presented and its performance gain over conventional random allocation strategy is numerically assessed
A Novel Exponential Link Error Prediction Method for OFDM Systems
Coded multicarrier techniques combined together with link resources adaptation algorithms are the key technologies toward efficient high-data-rate communications over wireless fading channels. This paper contributes with a novel accurate yet simple method to predict at the transmitter the link performance of bit-interleaved coded (BIC) orthogonal frequency division multiplexing (OFDM) links, which offers appealing features when compared with conventional techniques. Its effectiveness is confirmed through extensive simulation results obtained over typical wireless channel environments
A Pragmatic Bit and Power Allocation Algorithm for NOFDM Signalling
In this paper, a novel pragmatic bit and power allocation algorithm for Non Orthogonal Frequency Division Multiplexing (NOFDM) systems is presented. It is based on the well-known Campello approach and takes into account the lack of orthogonality between adjacent waveforms. Simulation results in a typical NOFDM wireless applicative scenario show the effectiveness of the proposed algorithms
A Low-Complexity Spreading-Code Allocation Strategy for Reduced-PAPR MC-CDMA Transmissions
In this contribution we demonstrate that the peak-to-average power ratio (PAPR) of a Multi-Carrier Code Division Multiple Access (MC-CDMA) signal can be suitably minimized by resorting to a judicious strategy for the allocation of the spreading signature codes. A low-complexity implementation of the proposed strategy is presented and its performance gain over conventional random allocation strategy is numerically assessed