This letter presents a novel multimodal biometric recognition algorithm based on complex kernel principle component analysis (CKPCA). CKPCA generalizes kernel principle component analysis (KPCA) method for complex field to perform feature fusion and classification. Iris and face are used as two distinct biometric modals to test our algorithm. Experimental results show that the proposed algorithm achieves much better performance than other conventional multimodal biometric algorithms.
Multiple Description Coding (MDC) is a new developed method to overcome fading in wireless communications. It enhances the robustness of information transmission over non-prioritized and unpredictable networks. A novel MDC framework for images based on the Space-Frequency Quantization (SFQ) algorithm is proposed in this paper. The redundancy is introduced through the improved zerotree quantization and the simple odd-even estimation method. In comparison with other schemes, the simulation results show the efficiency of the proposed method.
A novel compact wide bandpass filter is proposed by cascading two square-ring resonators, a quarter wave length short-stub and a quarter wavelength open-stub. This filter offers wide passband, with high out-of-band rejection and suppression of second spurious harmonic. Design procedure of a filter at 1GHz with 50% fractional bandwidth is presented showing good agreement between simulation and experimental results.
A 1-bit full adder cell based on majority function is designed and simulated. In this design the time consuming XOR gates are eliminated. Low-power consumption is targeted in implementation of our design. The circuit being studied is optimized for energy efficiency at 0.18-µm CMOS process technology. The new circuit has been compared to the previous work based on power consumption, speed and power delay product (PDP). HSPICE and Cadence simulations show that the proposed adder can work more reliably at different range of supply voltage. The proposed design has the best PDP in comparison with the others.
A novel low power time-mode comparator with enhanced resolution and speed is proposed in this paper. The comparator incorporates a symmetrical input time-to-digital converter (TDC) and a highly dynamic voltage-to-time converter (VTC). Energy reduction is achieved mainly through the use of capacitor discharge automatic switch-off and inverter clocking. The combined effect of the low timing requirement and capacitor voltage presetting enables significant precision and speed improvements. Simulations in a 0.18um process show that the comparator can be clocked at 38MHz, draws less than 0.4pJ energy from supply and can resolve voltages as low as 10µV.
The aim of this study was implementation of a wireless patch system that can predict a patient's body temperature. The proposed patch can predict the body temperature from the skin temperature and sweat rate by using a modified Pennes bio-heat transfer equation. The proposed patch was small and lights enough to be attached to the patient's skin, and a small skin temperature transducer was built-in the patch. Further, the sweat rate was measured by using humidity sensors while the sweat was evaporating. The proposed patch was compared with commercial body temperature measuring device, and the results were found to be correlated.
In this paper, we propose DFT Beamspace Matrix pencil (BMP) method for direction of arrival estimation (DOA). The DFT beamspace approach has the advantage of reduced computational complexity due to converting complex computations (in Matrix Pencil method) into real ones along with the inherent ability to operate in a reduced beam-space in situations where some priori information is available about the DOAs. Furthermore, a novel Multiple Invariance BMP (MBMP) method is also developed and it is shown through simulations that its reduced beamspace version has comparable performance to the existing Unitary Matrix Pencil method (UMP) with lower computational cost.
This paper proposes a new SHA-1 architecture to exploit higher parallelism and to shorten the critical path for Hash operations. It enhances a performance without significant area penalty. We implemented the proposed SHA-1 architecture on FPGA that showed the maximum clock frequency of 118MHz allows a data throughput rate of 5.9Gbps. The throughput is about 26% higher, compared to other counterparts. It supports cryptography of high-speed multimedia data.
We confirm the tolerance of our proposed wavelength-swept wavelength division multiplexing (WDM) access system to four-wave mixing (FWM) crosstalk induced during fiber transmission. Since wavelength-swept light is employed as the carrier in the proposed system, there is little mutual interaction between different channel signals. Therefore, the tolerance to FWM crosstalk of the proposed technique is superior to that of conventional methods based on continuous-wave carriers. As a proof-of-concept, we perform experimental 10- and 20-km single-mode fiber transmissions of four-channel 1.25Gb/s/ch WDM signals with a 12.5GHz spacing, and show that FWM crosstalk has no serious impact even with a high optical power of +19dBm.
A signaling approach for LR-WPAN is presented for reliable communications in frequency-selective channels. The scheme exploits cyclic sequences on time domain and performs the receiver operation on frequency domain to effectively suppress the channel effects, which considerably enhances the receiver performance for LR-WPAN under frequency-selective channels.
This letter introduces a novel passive beamformer which uses Bridge function sequence as spreading sequence weights for every antenna element. The set of Bridge function sequences have zero correlation zones (ZCZs) in their cross-correlation functions (CCFs). Due to the ZCZ properties of Bridge function sequences, the introduced passive beamformer features a much better performance on avoiding synchronization errors than the passive beamformers utilizing other spreading sequences without ZCZ.The theoretical justification of the proposed approach is presented in detail and the achievable performance is verified through computer simulations.
Pulse progagation on nonlinear transmission lines (NLTLs), which are transmission lines with regularly spaced Schottky varactors, is investigated for the amplification of short pulses. It is found that the soliton developed in an NLTL experiences an exponential amplitude growth, when it couples with a co-existing voltage edge.