Orthogonal Frequency Division Multiplexing (OFDM), which is a multicarrier modulation scheme, splits high data rate information symbols into lower rate parallel data streams and transmits this parallel information on different orthogonal carriers. The loss of orthogonality among subcarriers causes inter-carrier interference (ICI) which affects both channel estimation and detection of OFDM data ...

Assessment of exposure to airborne endotoxins has been studied for several years, especially in occupational environments, but a large number of procedures are used for sampling and analysis. This lack of standardization makes it very difficult to compare results and set internationally accepted threshold limit values (TLVs) or occupational exposure limits (OELs) for endotoxin exposure. This pa...

OFDM is a multicarrier modulation technique in which a high rate bit stream is split into N parallel bit-streams of lower rate and each of these are modulated using one of N orthogonal sub-carriers. In a basic communication system, the data is modulated onto a single carrier frequency. OFDM is a promising candidate for achieving high data rates in mobile environment because of its multicarrier ...

To construct the lumped spring-mass model considering the occupants for the offset frontal crash, the SISAME software and the NHTSA test data were used. The data on 56 kph 40% offset frontal vehicle to deformable barrier crash test of a MY2007 Mazda 6 4-door sedan were obtained from NHTSA test database. The overall behaviors of B-pillar and engine of simulation models agreed very well with the ...

OFDM is a multicarrier modulation technique in which a high rate bitstream is split into N parallel bit-streams of lower rate and each of these are modulated using one of N orthogonal sub-carriers. Orthogonal Frequency Division Multiplexing (OFDM) is an emerging multi-carrier modulation scheme, which has been adopted for several wireless standards such as IEEE 802.11a and HiperLAN2. In a basic ...

We report on the charge offset drift (time stability) in Si single electron devices (SEDs) defined with aluminum (Al) gates. The size of the charge offset drift (0.15 e) is intermediate between that of Al/AlO(x)/Al tunnel junctions (greater than 1 e) and Si SEDs defined with Si gates (0.01 e). This range of values suggests that defects in the AlO(x) are the main cause of the charge offset drift...

We present a novel algorithm for estimating the Carrier Frequency Offset (CFO) in an OFDM receiver. The algorithm is based on locating the spectral minimas within null subcarriers embedded in the spectrum. This is done by using a scaled DFT algorithm to calculate the spectrum of the OFDM symbol around the null subcarrier, followed by averaging the absolute square of the amplitude. The method is...

In this contribution we analyzed and compared the bit error rate performance for MC-CDMA (multicarrier codedivision multiple access) systems using IFFT/FFT (inverse fast Fourier transform/fast Fourier transform) and conventional correlation receiver over a frequency selective Rayleigh fading channel. Carrier frequency offset is considered in the analysis with either equal gain combining or maxi...

Based on the need of MF-TDMA signal monitoring, this paper investigates the estimation method for frequency offset and carrier phase. The procedure for timing recovery is introduced, and then an effective algorithm is deduced for estimating carrier frequency and phase. The proposed open-loop algorithm demands no preambles and has a wide capture range. In addition, the overall block diagram of a...

In this paper we present an analytical approach to evaluate the M-QAM symbol error rate (SER) of Alamouti space time coded OFDM direct conversion receivers subject to carrier frequency offset (CFO), channel estimation errors, outdated channel state information, limited ADC resolution and flat receiver I/Q imbalance in Rayleigh time and frequency selective fading channels. The SER is numerically...