Research methods to increase the capacity of telecommunication broadband radioaccess systems, taking into account the requirements for error-rate performance
We propose a new generalized integrated approach for developing effective methods to increase the capacity of broadband radioaccess systems (BRAS) while providing the required error-rate performance and taking into account their characteristics, based on the interaction between system resources: energy and band. We obtained methods for improving the capacity of BRAS based on mathematical models, procedural, structural and systemic solutions for the effects of the time varying fading channel, thereby creating scientific basis for the creation of new next generation BRAS.
We established tecniques and methods to improve capacity of BRAS, while ensuring the required interference immunity towards improving band resource: increasing spectral efficiency through the use of space-time signal processing, improving the management of resource allocation and expansion band frequency bandwidth channel .
Mathematical models of 2nd order statistics for diversity and spatial multiplexing (MIMO) radiosystems with support for mobility were derived in the form of functional dependencies for the fading signal distributions of Rayleigh, Rice, Nakagami and Veybula were introduced.
Mathematical models of the probability of bit error for different fading channel distribution approximated by Nakagami-m were introduced. We proposed analytical expressions for the error rate of the OFDM system with Nakagami-m fading channel.
A projection method for spatial separation of users, based on the weight vector orthogonalization spatial processing at the base station that does not require evaluation of directions of signal arrival.
The mathematical model of the outage probability in a cellular multiple-antenna BRAS with Rice fading was introduced, the analytical expression for the approximation of outage probability was derived, as well as an analytic expression for the asymptotic variance of estimates of mutual information on cellular multiple-antenna BRAS.
We proposed a method for assessing the impact of channel parameters separation for BRAS, which can improve the capacity of BRAS with appropriate mathematical equations, which, unlike existing account for priority allocation of bandwidth multi-service BRAS and its limitations and will implement adaptive configuration approaches to the distribution service.
The mathematical model of broadband wireless access with Relay distribution is discussed, which allows the coordination of base stations to double the capacity.
A new method of allocating radioresources OFDMA system downlink based on partial knowledge of CSI is given. Sensitivity of the proposed method of distribution for accuracy CSI is studied.
For radio with MIMO-OFDM and space- time coding , a new algorithm for channel estimation with adaptation to a level of selectivity is proposed, which provides a gain in computational complexity.
The method of countering unpredictable bandwidth reduction as a result of the attacks of denial of service on the part of one of the connected subscribers is discussed.