Resource allocation for multicarrier CDMA systems in ultra-wideband communications

Abstract

Abstract-Ultra-wideband (UWB) is a fast emerging technology that has attracted considerable interest in short range, high data rate wireless personal area networks (WPAN) applications. One of the main candidates for WPAN standardization is the multiband orthogonal frequency division multiplexing (MB-OFDM), supported by the Multiband OFDM Alliance (MBOA). In this paper, we propose a new lowcomplexity resource allocation algorithm applied to a spread spectrum multicarrier multiple-access (SS-MC-MA) waveform, which is new for high data rate UWB applications. The proposed scheme aims at maximizing the system's throughput while taking into consideration the WPAN environment and respecting the OFDM parameters of the MBOA solution. The adaptive allocation algorithm applied to OFDM and SS-MC-MA leads to roughly double the throughput compared to the MBOA solution at low attenuation levels. Furthermore, at high attenuation levels, SS-MC-MA outperforms the adaptive OFDM. Hence, we conclude that the proposed adaptive SS-MC-MA can especially be advantageously exploited for high attenuation UWB applications.Index Terms-Information theory, multicarrier codedivision multiple-access (MC-CDMA), resource allocation, spread spectrum, ultra-wideband technology, wireless communications.

Adaptive Spread Spectrum Multicarrier Multiple-Access for UWB Systems

“…Previous resource allocation studies have been proposed for the MBOA model [5]. In this paper, we propose a new UWB waveform based on a spread spectrum multicarrier multiple-access (SS-MC-MA) scheme [6] respecting the OFDM parameters of the MBOA solution, and we propose an efficient low-complexity resource allocation algorithm applied to the SS-MC-MA scheme in order to maximize the total system throughput, while respecting the FCC regulations. Furthermore, we propose a new technique that maximizes the throughput by dynamically distributing the time-frequency codes that provide frequency hopping between users.…”

Adaptive Multi-Carrier Spread-Spectrum with Dynamic Time-Frequency Codes for UWB Applications

“…This scheme is applied to UWB while respecting the OFDM parameters of the MBOA solution [6]. The spreading is in the frequency domain in order to improve the signal robustness against the frequency selectivity of the UWB channel and against narrowband interference.…”

“…6 GHz spectrum for unlicensed use of UWB devices [1]. The FCC imposed a power spectral density (PSD) limit of -41.25 dBm/MHz in order to reduce interference with existing spectrum allocations.…”