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WiMAX is a broadband wireless technology based on IEEE802.16 standards family, which defines the physical (PHY) and medium access control (MAC) layers and makes several possible configurations available along with non-mandatory options. WiMAX is a new OFDM based technology and promises to combine high data rate services with wide area coverage. In this paper, the performance of WiMAX PHY layer is...
We present analytical expressions to calculate information spectral efficiency capacity of single mode fiber transmission in presence of fiber nonlinearity. We also present preliminary characterization and analysis of channel capacity for few-mode fiber transmission.
We investigate the problem of blind spectrum sensing at a secondary user of an orthogonal frequency-division multiplexing primary signal impaired by transmit I/Q imbalance. We derive a simple closed-form expression for the generalized likelihood ratio test as a function of the received signal only, i.e. without requiring any knowledge of the channel response, noise statistics, or I/Q imbalance parameters...
In a multiuser channel signals are corrupted due to Additive White Gaussian Noise (AWGN) and Inter Carrier Interference (ICI). Orthogonal Frequency Division Multiplexing (OFDM) receiver detects the symbols or bits and estimates the parameters. Wavelet Packet Modulation (WPM) is applied to the received symbols that have been previously coded at the transmitter by a special code. The final result obtained...
We consider distributed detection of an orthogonal frequency-division multiplexing (OFDM) random source using a cooperative set of sensors. Assuming that the observations of different sensors are independent, we derive/propose several frequency-domain detectors: the Neyman-Pearson detector for known SNRs and noise variances and three generalized likelihood ratio detectors for unknown SNRs and/or noise...
We propose a factor-graph-based approach to joint channel, impulse, symbol and bit estimation (JCISB) of LDPC-coded orthogonal frequency division multiplexing (OFDM) systems in impulsive noise environments. Impulsive noise arises in many modern wireless and wireline communication systems, such as cellular LTE and powerline communications, due to uncoordinated interference that is much stronger than...
This paper addresses the performance of the Multiple-Input-Multiple-Output(MIMO)-Orthogonal Fre-quency Division Multiplexing (OFDM), MIMO-OFDM communication system in environments where the interfering noise exhibits non-Gaussian behavior due to impulsive phenomena. It presents the design and simulation of an adaptive receiver technique that aims to minimize the effect of impulsive noise on the performance...
A direct-conversion receiver (DCR) reduces the power consumption and cost. However, DCR in Orthogonal frequency division multiplex (OFDM) systems suffer from IQ imbalance. Until this time, many algorithms are proposed to compensate IQ imbalance in OFDM. However, the complexity is still considerable work. On the other hand, time-frequency interferometry-OFDM (TFI-OFDM) system has been proposed to achieve...
A novel approach involving selective channel signaling is proposed to achieve significant reductions in power requirements in OFDM. It is shown that by using only a subset of the available channels, savings in power can be achieved without sacrificing channel capacity.
Energy efficiency and spectral efficiency of a Large Scale Antenna System in both dense urban and suburban multi-macro-cellular scenarios are quantified using a new total energy efficiency model, which consists of a rigorous capacity lower bound and a power model accounting for RF generation, LSAS critical computing and a per antenna internal power consumption for other analog electronics and A/D...
Power Line Communication (PLC) on aircraft is a potential technology to integrate the power and communication system for decreasing the weight and volume of the cables onboard. However, electromagnetic noise in power line made it a rush environment for data transmission. Especially, the narrowband interference in the frequency domain and the impulsive noise in the time domain are the most harmful...
Existing methods of self-interference cancellation have greatly reduced the strong self-interference signal for the practical design of Full-Duplex (FuDu) wireless systems. However, current FuDu wireless is hard to be put into practice due to the reason that residual self-interference after interference cancellation is still much stronger than the thermal noise. In this paper, a wideband FuDu OFDM...
Ranging performance is a fundamental and crucial figure of merit for any position estimation technique. Cooperative positioning requires accurate range estimation with low latency. Common solutions employ time slots to sequentially range among all possible mobile nodes. In this case the number of ranging links increases quadratically with the number of users which increases latency significantly....
Sampling frequency offset (SFO) that occurs due to a sampling frequency mismatch between the transmitter and receiver oscillators is one of the main problem in the orthogonal frequency division multiplexing (OFDM) based digital terrestrial television (DTTV) system. The SFO can cause an intersymbol interference and an intercarrier interference that may degrade the performance of an OFDM system and...
One of the most serious disturbances in Power Line Communications (PLC) is produced by the presence of impulsive noise sources in the transmission line. This paper analyses how impulsive noise affects the PLC communication's performance from a theoretical and simulation point of view and proposes a signal processing method to enhance its robustness. Authors focus on a popular narrowband PLC solution...
Recently, there has been considerable interest to utilize the power line infrastructure for broadband communications. Power Line Communications (PLC) operate in the frequency range between 1.8MHz to 30MHz defined by the IEEE 1901 standard. Within this frequency range, a number of organizations and users occupy their own specific spectrum. As a result, spectrum notching and interference avoidance need...
Optimized frequency tones for the power line channel is presented from an experimental scenario. Four sets of frequency tones, grouped according to CENELEC's regulation on frequency use for narrow band power line applications are selected according to their signal-to-noise ratio (SNR) performance. COMBLOCKS, a prototyping hardware was used for the implementation. Often times, M-FSK/OFDM have been...
Vehicular networking is becoming an actual disruptive technology which is going to improve, first of all, the overall safety as well as the the driving experience. The standardization efforts are almost completed and the first implementation issues are becoming real. Despite the fact that the physical layer is very similar to the one of the Wi-fi standards, while the classical Wi-fi standards which...
DC distribution system is one of technologies for reducing the loss of electric power transmittion because the most of loads are recently driven by DC source. For a farther improvement of the efficiency, an optimum control of loads is required. Power line communication (PLC) is suitable for its communication. A simulation of a PLC for a DC distribution system based on orthogonal frequency-division...
Employing the low bitwidth, e.g. 1 bit or 2 bit analog-to-digital converter (ADC) can remarkably reduce the high power dissipation of ADC in the orthogonal frequency division multiplexing (OFDM) communications. However, the biterror-rate (BER) performance will be considerably undermined. In the paper, through deliberately reserving the subcarrier at the transmitter, the quantization distortion can...
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