En az enerjili kanal ve ağ kodlaması ve nano boyutta haberleşme üzerine uygulamaları

Channel coding, as indicated by Claude E. Shannon, is mostly used to achieve the capacity, by means of introducing redundancy to combat the effects of noise. In this thesis, an energy minimizing novel channel code (MEC) with controllable reliability is proposed for the first time. The motivation stems from the severe energy constraints of nano communications. Due to their tiny size, nanodevices can only supply a limited amount of energy. The need to optimize communication techniques for minimum energy includes the development of a novel channel code that provides reliability, while keeping the transmitter energy at minimum. We develop minimum energy channel code (MEC), which uses the idea of increasing the frequency of the modulation state that requires less energy. On-off keying (OOK) modulation is the simplest of such techniques and assumed to be the underlying modulation throughout the thesis. MEC provides the desired reliability with varying delay, when source set cardinality is less than the inverse of symbol error probability. The proposed channel code is shown useful in nanosensor networks. The performance of MEC is also evaluated considering the random interference due to multiple uncoordinated users in the ad-hoc nanonetworks. The theoretical maximum node density limit in an ad-hoc nanonetwork with reliable communications between the nodes is derived. Investigating delay via varying codeword length, rate-delay-energy tradeoffs with MEC are analyzed. Lastly, for the first time in the literature, network codes that minimize energy is developed in network coding nodes with two incoming edges. To minimize the overall network energy in in-two networks, each node is assumed to employ MEC with OOK. Therefore, MENC provides the best mapping between input edges and output edge of the coding node, that minimizes the average energy at the output of the coding node, by minimizing the average weight.