In this paper, a new algorithm for subcarrier and power allocation for the downlink of multiuser OFDM transmission is presented. The proposed algorithm is more stable and it offers a lower complexity and better performance than previous existing algorithms.

A novel hybrid channel estimator is proposed for multiple-input multiple-output orthogonal frequencydivision multiplexing (MIMO-OFDM) system with per-subcarrier transmit antenna selection having optimal power allocation among subcarriers. In practice, antenna selection information is transmitted through a binary symmetric control channel with a crossover probability. Linear minimum mean-square ...

Multi-Carrier Code Division Multiple Access MC-CDMA is a promising technology for supporting high data rate in next generation wireless networks. By combining MCCDMA technology with Multiple-Input Multiple-Output (MIMO) spatial mssultiplexing, data transfer rate can be enhanced. However, the performance of MCCDMA technology is limited by the multiple-access Interference (MAI) and InterCarrier I...

Cognitive Radio (CR), which aims to improve spectrum utilization by accessing the spectrum originally licensed to a primary system, is a promising concept. In cognitive radio system based on orthogonal frequency division multiplexing (OFDM), the optimized algorithms for sub-carrier power allocation share the problems of complex iterative calculation and difficult realization. In this case, a su...

A resource Allocation Problem for spectrum sharing in wireless communication system. Using multiinput multi-output orthogonal frequency division multiple ( MIMO-OFDM) is a very promising technology for enhancing the flexibility and efficiency of cellular and future communication systems. A joint optimization problem for resource allocation is solved by a combine scheme of multiple-input multipl...

In this paper, we propose novel algorithms for optimal power allocation towards video transmission in orthogonal frequency division multiple access (OFDMA) and multiple-input multiple-output (MIMO)-based 4G networks. A unique feature of the schemes is that they employ diversity dependent subcarrier power distribution relying on a discrete wavelet transform (DWT)-based hierarchical video decompo...

Orthogonal Frequency Division Multiplexing Access (OFDMA) relay system is a promising technique for increasing the capacity and the range of wireless communication systems. Dynamic resource allocation for OFDMA relay systems plays an important role in improving the system performance. However, most of the resource allocation algorithms are designed for the unicast traffics, and resource allocat...