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In this paper, a spike-based background light suppression ToF pixel is proposed. This pixel adopts a novel in-pixel background light suppression circuit. The in-pixel background light suppression circuit can realize effective self-suppression of the background light and convert the received infrared light intensity to the number of spikes. The proposed ToF pixel is designed in a 0.11µm CMOS image sensor technology with a physical size of 27.5 × 27.5µm2. Simulation results illustrate that the proposed pixel is capable of suppressing background light of 30dB BRS without filter. The ToF sensor with the proposed pixel can not only used in indoor applications but also used in high intensity background applications.

In this paper, an iterative sparse channel estimation for orthogonal frequency division multiplex (OFDM) communication system is investigated based on the sparse reconstruction by separable approximation (SpaRSA), which is regarded as one of the fastest algorithms for l 2 -lj problem and can obtain its global optimal solution. The proposed estimator comprised of thresholding is applied to detect channel taps. Then, a modified SpaRSA with adaptive regularization parameter is used to refine the estimation of nonzero channel taps. Simulation results for typical sparse channels show effectiveness of the proposed algorithm over other existing methods.

In this paper, a UWB pulse design method is proposed for the coexistence of UWB and IEEE 802.11a WLAN systems by using the raised cosine pulses. The simulation results show that the pulse spectrum satisfies the FCC mask and also avoids WLAN system. The comparison of bit error rate (BER) performance is presented by using the proposed pulse and the second-order derivative Gaussian pulse in the additive white Gaussian noise channel. It is shown that the proposed pulse has better BER performance than the second-order derivative Gaussian pulse and hence improves the performance of UWB systems.

The spectrum compatibility of UWB and IEEE 802.11a WLAN systems is investigated in this paper. A UWB pulse designed method is developed based on the cognitive radio technology and Parks-McClellan algorithm. Under the three-dimensional interference model, the interference performance of UWB on WLAN is analyzed and simulated. The simulation results show that the pulse spectrum not only satisfies the requirement of FCC mask but also avoids WLAN system. The comparison of bit error rate performance is presented by using the proposed pulses and the fifth-order derivative Gaussian pulse to the time hopping UWB system in the additive white Gaussian noise channel. And the proposed pulse has better bit error rate performance than the fifth-order derivative Gaussian pulse.

Granite aggregate can be used in the construction of asphalt pavement. Through the experimental study, the relationship of granite microstructure and its abilities of strength, water absorption and adhesion are given in this paper. The factors that affect the compressive strength of granite rocks include rock structure, mineral composition, weathered degree of the rock, cracks and phenocryst. The adhesion of different granite aggregate is discrepant. The factors that affect the adhesion of granite aggregate include rock structure, mineral composition, surface characteristics of the rock, pore and phenocryst. Contact angle has good correlation with the adhesion test conclusion, contact angle can be quantified to reflect the differences in adhesion of different granite. The pore size of aggregate porosity has effect on the water absorption of aggregates, the smaller the aperture is, the more easily aggregate absorbs water. Pore diameter will also affect the aggregate's absorption of asphalt, thus affecting the optimum asphalt content of the asphalt mixture.

This paper makes a study of an algorithm of fault location for double transmission line on the same tower. The algorithm is based on model of distributed parameters. The location equation set is deduced and the solving of the equation set is researched.

Adaptive pulses in ultra wideband (UWB) wireless communication system are applied by forming notches at some frequencies as a way to suppress its interference to the existing narrowband systems. This paper proposes a novel method in designing adaptive pulses by using the Cognitive Radio technology and Parks-McClellan algorithm. Cases of arbitrary narrowband interferences are studied. The simulation results show that the power spectrum density of the proposed pulses not only meets the constraints of the FCC indoor mask but also avoid the narrowband interferences. The comparison of bit error rate performance is presented by using the proposed pulses and the fifth-order derivative Gaussian pulse to the time hopping UWB system in the additive white Gaussian noise channel. With low computational complexity, the proposed pulses have lower bit error rate and hence improve whole UWB system performance.

Adaptive pulses in ultra wideband (UWB) wireless communication system are characterized by forming notches at some frequencies as a way to suppress its interference to licensed narrowband users. This paper proposes a novel method in designing adaptive pulses by using the Cognitive Radio technology and Parks-McClellan algorithm. One case of arbitrary narrowband interference is studied. The simulation results show that the power spectrum density of the proposed pulses meets the constraints of the FCC indoor mask. The comparison of bit error rate performance is presented by using the adaptive pulses and the fifth-order derivative Gaussian pulse to the time hopping UWB system in the additive white Gaussian noise channel. With the low computational complexity, the proposed pulses have lower bit error rate than the fifth-order derivative Gaussian pulse and hence make the whole UWB system reduce narrowband interference.

This paper presents a mean square error (MSE) analysis of the recursive least square (RLS) algorithm for system identification over wide-sense stationary uncorrelated scattering (WSSUS) fading channels. A new sum-of-sinusoids (SOS) model for modeling fading channel is proposed. Unlike most of RLS analyses, our analysis takes the correlation of the inverse of correlation matrix into account and hence yields an improved recursive formula for the MSE, which can be computed recursively with the information of the second order statistics of fading channels. The steady state MSE of RLS is derived for Clarke's model. It is shown that the MSE analysis using the SOS model have much better agreement with experimental results than the AR model.