Abstract: One of the main challenges in MIMO-OFDM system
to achieve the expected performances in terms of data rate
and robustness against multi-path fading channels is the channel
estimation. Several methods were proposed in the literature based on
either least square (LS) or minimum mean squared error (MMSE)
estimators. These methods present high implementation complexity
as they require the inversion of large matrices. In order to overcome
this problem and to reduce the complexity, this paper presents
a solution that benefits from the use of the STBC encoder and
transforms the channel estimation process into a set of simple
linear operations. The proposed method is evaluated via simulation
in AWGN-Rayleigh fading channel. Simulation results show a
maximum reduction of 6.85% of the bit error rate (BER) compared to
the one obtained with the ideal case where the receiver has a perfect
knowledge of the channel.
Abstract: A low-complexity, high-accurate frequency offset
estimation for multi-band orthogonal frequency division multiplexing (MB-OFDM) based ultra-wide band systems is presented regarding different carrier frequency offsets, different channel frequency
responses, different preamble patterns in different bands. Utilizing a
half-cycle Constant Amplitude Zero Auto Correlation (CAZAC) sequence as the preamble sequence, the estimator with a semi-cross
contrast scheme between two successive OFDM symbols is proposed. The CRLB and complexity of the proposed algorithm are derived.
Compared to the reference estimators, the proposed method achieves
significantly less complexity (about 50%) for all preamble patterns of the MB-OFDM systems. The CRLBs turn out to be of well performance.
Abstract: Today due to rising levels of housing- necessities,
several problems have been raised regarding to urban quality of life.
The aim of the research is to study social and spatial aspects of
housing environment and to find out their interaction with the urban
quality of life. As a case of study two pilot areas of Famagusta city in
North Cyprus, were selected: Baykal, considered as an established
urban district and Tuzla, a newly developed peri-urban district. In
order to determine urban quality of life in planning and developing of
housing areas, social and spatial aspects of selected areas have been
examined, differences between them according to the planning policy
have been pointed out, advantages and disadvantages of housing
planning have been found. As a practical implementation of the
research a number of households in each selected area have been
interviewed in order to draw a conclusion.