In this paper, an efficient and fair algorithm for resource management in MIMO-OFDM systems is proposed. The system used for this analysis is the downlink of multi-user MIMO-OFDM system. Based on channel state information (CSI), the base station (BS) employs singular value decomposition (SVD) to transmit the MIMO channel into parallel subchannels for each subcarrier, and then subcarriers, are a...

In this paper we provide three contributions to the field of channel sounding waveform design in asynchronous Multi-user (MU) MIMO systems. The first contribution is a derivation of the asynchronous MU-MIMO model and the conditions that the sounding waveform must meet to independently resolve all of the spatial channel responses. Next we propose a chirp waveform that meets the constraints and w...

In this paper, we propose the combination of Multi Carrier (MC) OFDM/OQAM modulation and CDMAcalled MC-CDMA-OQAM system with Space Time (ST) coding in a multi user context. This combination takes advantages from multicarrier modulation, spread spectrum and spatial time diversity. Indeed, the use of OFDM has proved its ability to fight against frequency selective channels but the insertion of gu...

The application of OFDM within a multi-user downlink scenario is considered. Thereby, two problems occur. First, due to OFDM, the transmit signal exhibits a large peak-to-average power ratio (PAR). Second, the multi-user interferences have to be equalized (or precoded) at the transmitter side. In this article, we address combined precoding and PAR reduction. As precoding schemes sorted Tomlinso...

Satisfaction of different QoS demands for various broadband services in wireless networks requires that multi-user packet scheduling intelligently use both channel state information (CSI) and queue state information (QSI). A combination of queuechannel-aware scheduling and power/rate allocation on each transmit dimension is known as “cross-layer resource allocation”. This thesis investigates va...

Alomouti’s space-time coding scheme for Multi-Input Multi-Output (MIMO) system has drawn much attention in 4G wireless technologies. Orthogonal frequency division multiplexing (OFDM) is a popular method for high data rate wireless transmission. OFDM may be combined with antenna arrays at the transmitter and receiver to increase the diversity gain and enhance the system capacity on time variant ...

We propose a novel resource allocation scheme, which can reduce MAP overhead and maximize the throughput in the MIMO-OFDM systems. In the message based broadband access system, we need to minimize the MAP overhead since the excessive MAP overhead causes degradation of system throughput. Increasing the size of resource allocation unit can reduce MAP overhead. However, multiuser diversity gain be...

in recent years, wavelet packet modulation ofdm (wpm-ofdm) signals have been introduced for radar applications. these signals have important properties such as inherent high range resolution and high resistance of radar system against jamming reception. this paper investigates the problem of designing these family of signals according to the following criteria: constrained maximization of the d...