In this thesis we study the design of universal codes for parallel Gaussian channels with 2 sub-channels present. We study the universality both in terms of the uncertainty in the relative quality of the two sub-channels for a fixed maximum rate, C*, and in terms of the uncertainty of the achievable maximum rate. In our architecture, we will convert the parallel Gaussian channel into a set of s...

Similar to traditional wireless sensor networks (WSN), the nodes only have limited memory and energy in low-duty-cycle sensor networks (LDC-WSN). However, different from WSN, the nodes in LDC-WSN often sleep most of their time to preserve their energies. The sleeping feature causes serious data transmission delay. However, each source node that has sensed data needs to quickly disseminate its d...

In this paper, we study the bit error rate (BER) and the frame error rate (FER) performance for rateless coding aided cooperative communications using an effective protocol over additive white Gaussian noise (AWGN) channels. During the collaborative phase, the proposed protocol adopts an adaptive demodulation (ADM) scheme considered channel state and the partial cooperation scheme depending on ...