80 research outputs found
Adaptive resource allocation within three-stage OFDM relay networks
In this work we consider OFDM transmission, due to its potential for meeting the stringent quality of service (QoS) targets of next-generation broadband distributed wireless networks, over three-stage relay networks. In particular, we examine distributed adaptive space-frequency coding for generally asynchronous links composed of four transmit and/or receive antennas, i.e. exploiting quasi-orthogonal and extended-orthogonal coding schemes. The successful deployment of these closed-loop methods is dependent upon channel state information (CSI) being available for each stage of the network. Taking the maximum end-to-end data rate as the optimal criterion, an adaptive resource allocation (RA) scheme suitable for a wide range of signal-to-noise-ratios (SNRs) and a prescribed transmit power budget is proposed to distribute appropriate resources to each stage based on the channel state information (CSI) and knowledge of the network topology
Towards a Seamless Future Generation Network for High Speed Wireless Communications
YesThe MIMO technology towards achieving future
generation broadband networks design criteria is presented.
Typical next generation scenarios are investigated. The MIMO
technology is integrated with the OFDM technology for effective
space, time and frequency diversity exploitations for high speed
outdoor environment. Two different OFDM design kernels (fast
Fourier transform (FFT) and wavelet packet transform (WPT))
are used at the baseband for OFDM system travelling at
terrestrial high speed for 800MHz and 2.6GHz operating
frequencies. Results show that the wavelet kernel for designing
OFDM systems can withstand doubly selective channel fading for
mobiles speeds up to 280Km/hr at the expense of the traditional
OFDM design kernel, the fast Fourier transform
On the performance of multicarrier CDMA (MC-CDMA) systems with transmit diveristy
Master'sMASTER OF ENGINEERIN
- …