International Journal of Research in Wireless Systems, 2013
A combination of Multiple-Input Multiple-Output Spatial Division Multiplexing technology and Orth... more A combination of Multiple-Input Multiple-Output Spatial Division Multiplexing technology and Orthogonal Frequency Division Multiplexing technique, namely MIMO-OFDM SDM systems, has been well-known as a potential technology to provide high speed data transmission and spectrum e fficiency for modern wireless communications networks. Many technical papers have been evaluated the systems ba sed on theory analyses and/or computer simulation, but just few ones have investigated the systems based on FPGA design, which is an important step before going to manufac ture the integrated circuits. In the paper, we present our own design a nd implementation of three different MIMO-OFDM SDM systems on FPGA-based DSP Development Kit. Based on the design, we evaluate the bit-error rate performance of the systems and also consider the consumption of the FPGA elements in our design. The results have shown our successful des ign and implementation of the systems on FPGA hardware. CONCLUSIONS MIMO-OFDM SDM technology has been considered a candidate for high speed wireless data transmission net works because of its significant increase of channel capa city and use of spectrum efficiently. In the paper, we have investigated the systems based on hardware design and implementation. We have shown our detailed design of three differ ent systems on the FPGA-based DSP Development Kit. Based on the design, we have measured and evaluated BER performance of the systems. The results have shown that our design and implementation are successful. Here, we also considered the consumption of FPGA elements. It has shown the efficiency of our d esign.
Journal of Advanced Computational Intelligence and Intelligent Informatics, 2003
A complete, recursive axiomatization of a subsystem of Levesque’s only-knowing logic is given. Th... more A complete, recursive axiomatization of a subsystem of Levesque’s only-knowing logic is given. The sublogic is obtained by relaxing some of Levesque’s semantic conditions while keeping the most important definitions unchanged. The axiom system is obtained by adding an axiom of Humberstone to a subset of the set of Levesque’s axioms. The completeness result is proved using the subordination method of Hughes and Cresswell.
We propose in the paper a new solution to the so-called Logical Omniscience Problem of epistemic ... more We propose in the paper a new solution to the so-called Logical Omniscience Problem of epistemic logic. Almost all attempts in the literature to solve this problem consist in weakening the standard epistemic systems: weaker systems are considered where the agents do not possess the full reasoning capacities of ideal reasoners. We shall argue that this solution is not satisfactory: in this way omniscience can be avoided, but many intuitions about the concepts of knowledge and belief get lost. We shall show that axioms for epistemic logics must have the following form: if the agent knows all premises of a valid inference rule, and if she thinks hard enough, then she will know the conclusion. To formalize such an idea, we propose to \dynamize" epistemic logic, that is, to introduce a dynamic component into the language. We develop a logic based on this idea and show that it is suitable for formalizing the notion of actual, or explicit knowledge.
International Journal of Research in Wireless Systems, 2013
A combination of Multiple-Input Multiple-Output Spatial Division Multiplexing technology and Orth... more A combination of Multiple-Input Multiple-Output Spatial Division Multiplexing technology and Orthogonal Frequency Division Multiplexing technique, namely MIMO-OFDM SDM systems, has been well-known as a potential technology to provide high speed data transmission and spectrum e fficiency for modern wireless communications networks. Many technical papers have been evaluated the systems ba sed on theory analyses and/or computer simulation, but just few ones have investigated the systems based on FPGA design, which is an important step before going to manufac ture the integrated circuits. In the paper, we present our own design a nd implementation of three different MIMO-OFDM SDM systems on FPGA-based DSP Development Kit. Based on the design, we evaluate the bit-error rate performance of the systems and also consider the consumption of the FPGA elements in our design. The results have shown our successful des ign and implementation of the systems on FPGA hardware. CONCLUSIONS MIMO-OFDM SDM technology has been considered a candidate for high speed wireless data transmission net works because of its significant increase of channel capa city and use of spectrum efficiently. In the paper, we have investigated the systems based on hardware design and implementation. We have shown our detailed design of three differ ent systems on the FPGA-based DSP Development Kit. Based on the design, we have measured and evaluated BER performance of the systems. The results have shown that our design and implementation are successful. Here, we also considered the consumption of FPGA elements. It has shown the efficiency of our d esign.
Journal of Advanced Computational Intelligence and Intelligent Informatics, 2003
A complete, recursive axiomatization of a subsystem of Levesque’s only-knowing logic is given. Th... more A complete, recursive axiomatization of a subsystem of Levesque’s only-knowing logic is given. The sublogic is obtained by relaxing some of Levesque’s semantic conditions while keeping the most important definitions unchanged. The axiom system is obtained by adding an axiom of Humberstone to a subset of the set of Levesque’s axioms. The completeness result is proved using the subordination method of Hughes and Cresswell.
We propose in the paper a new solution to the so-called Logical Omniscience Problem of epistemic ... more We propose in the paper a new solution to the so-called Logical Omniscience Problem of epistemic logic. Almost all attempts in the literature to solve this problem consist in weakening the standard epistemic systems: weaker systems are considered where the agents do not possess the full reasoning capacities of ideal reasoners. We shall argue that this solution is not satisfactory: in this way omniscience can be avoided, but many intuitions about the concepts of knowledge and belief get lost. We shall show that axioms for epistemic logics must have the following form: if the agent knows all premises of a valid inference rule, and if she thinks hard enough, then she will know the conclusion. To formalize such an idea, we propose to \dynamize" epistemic logic, that is, to introduce a dynamic component into the language. We develop a logic based on this idea and show that it is suitable for formalizing the notion of actual, or explicit knowledge.
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