Sum-Power Minimization in OFDMA Networks with User Rate Constraints

State Sstimation over Fading Channels: Outage and Diversity Effects Kimmo Kansanen Department of Electronic and Telecommunications, Norwegian University of Science and Technology (NTNU), Norway Uncoded (analog) transmission of a scalar first-order Gauss-Markov process over fading channels is considered. This model is applicable in real-time applications and for settings such as wireless sensor networks with processing at the fusion center due to it simplicity and zerodelay property. The optimal MMSE estimator at the receiver is the Kalman filter with random instantaneous estimation error variance, assuming perfect channel estimation. We select the estimation error outage probability as a means of characterizing the estimation quality. This criterion depicts probabilistically how often the value of the instantaneous estimation error variance crosses a certain threshold. We first consider the SISO case and find an integral equation that characterizes the probability distribution function of the instantaneous estimation error variance for general fading channels. We then use the pdf to obtain the outage probability and find tight upper and lower bounds for Rayleigh fading channels and in the high SNR regime. Thereafter, we extend our study to the SIMO case and assuming d independent Rayleigh fading channels to transmit the signal, we find the pdf and outage probability for instantaneous estimation error variance. Finally, we prove that in the high SNR regime, the outage probability decreases with d-th power of SNR, analogous to the notion of diversity in the digital communications over fading channels. Theoretical Impact Analysis of Fading First Order Statistics of Channel Variation on Outage Probability of Cooperative Wireless Networks Presenter: Shen Qian School of Information Science, Japan Advanced Institute of Science and Technology (JAIST), Ishikawa, Japan