This paper presents a cost-effective CORDIC-based architecture for adaptive lattice filters. An implementation method for an ARMA lattice filter using the CORDIC algorithm has been proposed. The previously proposed method can provide a simple filter architecture; however, it has problems such as redundant structure and numerical inaccuracy. Therefore, by solving each problem we derive a new non-redundant filter architecture with improved numerical accuracy. The obtained filter architecture provides a low cost ARMA lattice filter in which high-precision data processing is feasible. In addition, the proposed architecture can be applied to AR-type lattice filters, so that it may have several applications in adaptive signal processing. The presented filter architecture is useful from a hardware point of view because it facilitates an effective VLSI design of various adaptive lattice filters.

We propose binary-quantized and spatio-temporally discretized network models of linear diffusion systems and investigate their filtering effect on single-bit sigma-delta (ΣΔ) modulated signals. The network consists of only one kind of elements that add ΣΔ modulated signals and quantize the sum in the form of single-bit signal. A basic one-dimensional network is constructed first. Then, the network is extended into two dimensions. These networks have characteristics equivalent to those of linear diffusion systems in both time and frequency domains. In addition, network noise caused by the quantization in the elements contains low-level low-frequency components and high-level high-frequency components. Therefore, the proposed networks have possibility to be used as signal propagation and diffusion media of ΣΔ domain filters.

Simply-typed term rewriting systems (STRSs) are an extension of term rewriting systems. STRSs can be naturally handle higher order functions, which are widely used in existing functional programming languages. In this paper we design recursive and lexicographic path orders, which can efficiently prove the termination of STRSs. Moreover we discuss an application to the dependency pair and the argument filtering methods, which are very effective and efficient support methods for proving termination.

The accuracy of channel estimation significantly affects the performance of coherent receiver in a DS-CDMA system. The receiver performance can be improved if an appropriate channel estimation filter is used according to the channel condition. In this paper, we consider the design of channel estimation filters for pilot channel based DS-CDMA systems. When a moving average (MA) FIR filter is used as the channel estimation filter (CEF), the tap size is optimized by minimizing the mean squared error of the estimated channel impulse response. Finally, the analytic design is verified by computer simulation. Numerical results show that the optimum MA FIR CEF provides near optimum performance, i.e., quite similar to that with the use of Wiener filter.

This paper describes synthesis of a complex RiCR filter with a finite transmission zero except zero frequency. The frequency response of the proposed filter is similar to the conventional elliptic filter. The proposed filter can be composed of fewer elements than the conventional one. A new kernel function is proposed. As an example, a fifth-order RiCR filter is designed. We compare the proposed filter with the conventional complex elliptic filter from the viewpoint of the frequency response and the number of the required elements.

A Gm-C filter using multiple-output transconductors suitable for reducing the chip area and power consumption is presented. The novel multiple-output transconductor is based on a translinear gain cell with a linearized input stage. Making good use of the linearized input stage, a simple common-mode feedback is also proposed for this multiple-output transconductor. Using the proposed technique, a 5th-order lowpass filter with two transmission zeros was designed and fabricated as a main part of a lowpass channel selection filter for UMTS receivers. A channel of the filter consumes 7 mA from a 2.7 V power supply and the integrated input-referred noise was 21 dBuV with 20 dB pass band gain. The proposed multiple-output technique saves roughly half the number of transconductors compared with the typical active ladder filter design. The proposed multiple-output transconductors achieve linearization and effective reduction while saving linearized input stages. They are suitable for a filter with small power consumption and small area.

This study proposed the new method to minimize distortion of the ST segment and noise deletion of ECG baseline wander. In general, the standard filter and adaptive filter are used to remove the baseline wander of the ECG. The standard filter, however, is limited because the frequency of the baseline signal is variable and the baseline wander's spectrum overlaps with the ST segment's spectrum, and for the adaptive filter, it is difficult to select the reference signal. This study proposed a new, structured adaptive filter that is to remove noise without reference signal using neural networks. In order to confirm performance, this paper used ECG data of MIT-BIHs and obtained significant results through the tests.

Software-Defined Radio (SDR) receiver has the ability of operating in a multi-mode environment and has wide applications. However, efficient recognition of the currently active modulation system in real-time is a major problem faced by many applications. In this paper, an efficient method for the recognition of modulation system in a SDR receiver is proposed. The method is a classical two-stage approach based on (i) decision feature extraction and (ii) modulation system classification. In the first stage, decision features are extracted by the use of digital quadrature polyphase filter. In the second stage, an efficient parallel decision algorithm is proposed to classify the active modulation type. This proposed algorithm is proof to be more efficient than the conventional type of decision-tree approach. The complete recognition system is implemented using MATLAB. Simulation result shows that the proposed method achieved good robustness even with the presence of band-limited Additive White Gaussian Noise (AWGN). The overall successful recognition rate of 98.5% can be achieved even at a low signal-to-noise ratio (SNR) of 8 dB.

A new concept of changing inductance values has been proposed, where a part of meander inductor is short circuited to reduce effective line length. Microwave characteristics of the short-circuited meander inductors and the meander inductor without the short circuit have been designed and fabricated on resin circuit boards. The reduction of inductance values by 40% has been successfully realized for the microwave frequency range from 0.5 GHz to 5 GHz for both designed and measured results. Using the proposed structure, low pass filters having two different cut-off frequencies have been designed and tested. Measured cut-off frequency changed 3.0 GHz to 4.2 GHz.

A new method to extract retinal blood vessels from a colour fundus image is described. Digital colour fundus images are contrast enhanced in order to obtain sharp edges. The green bands are selected and transformed to correlation coefficient images by using two sets of Gaussian kernel patches of distinct scales of resolution. Blood vessels are then extracted by means of a new algorithm, directional recursive region growing segmentation or D-RRGS. The segmentation results have been compared with clinically-generated ground truth and evaluated in terms of sensitivity and specificity. The results are encouraging and will be used for further application such as blood vessel diameter measurement.

A new robust extended Kalman filter is proposed for the discrete-time nonlinear systems with norm-bounded parameter uncertainties. After linearization of the nonlinear systems, the uncertainties described by the energy bounded constraint can be converted into an indefinite quadratic cost function to be minimized. The solution to the minimization problem is given by the extended Kalman filter derived in a Krein space, which leads to a robust version of the extended Kalman filter. Since the resulting robust filter has the same structure as a standard extended Kalman filter, the proposed filter can be readily designed by simply including the uncertainty terms in its formulas. The results of simulations are presented to demonstrate that the proposed filter achieves the robustness against parameter variation and performs better than the standard extended Kalman filter.

In this paper, the method of locating multiple transmission zeros by the tap-coupling technique is described for bandpass filters (BPFs), using short-ended λ/2 resonators and its application to a duplexer. First, the method of locating the transmission zero using the short-ended λ/2 resonators is examined with various excitation methods. We focus on four types of short-ended λ/2 resonators: the end-coupling type, tap-coupling type, capacitive tap-coupling type and inductive tap-coupling type. Secondly, the BPFs based on the basic characteristics of the respective resonators are proposed and designed on the basis of a general filter theory with narrow band approximation. Lastly, we propose and design new duplexers consisting of the proposed BPFs. The results lead to the conclusion that the basic characteristics of the short-ended λ/2 resonators are useful for realizing a BPF with multiple transmission zeros and a high-performance duplexer fabricated without increasing the number of elements.

This paper reports the design and fabrication of a miniaturized superconducting microstrip line filter using YBCO film on MgO. The filter's resonators are shaped in a double spiral, and the size of the resonators is optimized from the standpoint of the unloaded Q-factor. The 15-pole bandpass filter that has the center frequency of 1.95 GHz and the bandwidth of 20 MHz is designed in the size of 9.7 44 mm. The simulated S-parameter characteristics of the filter is corresponding to the initial design parameters. We fabricated the filter on an MgO substrate with a diameter of 2 inches. The filter had very sharp cutoff and a very low insertion loss of 0.14 dB.

A conventional waveguide filter is usually composed of a waveguide which is set with irises and posts inside. When dielectric material is not loaded inside the filter, the filter is too large to mount it on a planar circuit even if the frequency band is as high as the millimeter-wave band. In this paper, we propose a dielectric waveguide filter using LTCC (Low-Temperature Co-fired Ceramics) which can be mounted on a planar circuit. The dielectric waveguide filter using LTCC is composed of a dielectric-loaded waveguide including posts (via holes) and TEM-TE10 converters. The design method of the filter is shown and comparison of the simulated and the experimental results in the 6 GHz band is demonstrated. The simulated results agreed well with the experimental ones. To improve the attenuation characteristics, particularly at the above pass-band frequencies, an attenuation pole is added using a cross patch set inside the LTCC filter in the 25 GHz band. The effect of the cross patch is confirmed using the same simulation method as used for the 6 GHz band. As a result, it is confirmed that the cross patch is very useful for improving the attenuation characteristics at the above pass-band frequencies.

A novel reconfigurable architecture has been proposed for a mobile terminal receiver that can drastically reduce power dissipation dependant on adjacent channel interference. The proposed design can automatically scale the number of filter coefficients and word length respectively by monitoring the in-band and out-of-band powers. The new architecture performance was evaluated in a simulation UTRA-TDD environment because of the large near far problem caused by adjacent channel interference from adjacent mobiles and base stations. The UTRA-TDD downlink mode was examined statistically and results show that the reconfigurable architectures can save an average of up to 75% power dissipation respectively when compared to a fixed filter length of 57 and word length of 16 bits. This power saving only applies to the filter and ADC, not the whole receiver. This will prolong talk and standby time in a mobile terminal. The average number of taps and bits were calculated to be 14.98 and 10 respectively, for an outage of 97%.

This paper focuses on the realization of low spurious responses by various bandpass filters (BPFs) using open-ended λ/2 resonators. The first part of this paper gives the resonance characteristics of the open-ended λ/2 resonators when the excitation methods are chosen. Secondly, various BPFs obtained with our methodology are provided. For constructing the BPF, (1) point-coupled resonators, (2) comb-line resonators, (3) quasi comb-line resonators and (4) parallel-coupled resonators are used. It is verified that the presented BPFs can be used to obtain low spurious responses both theoretically and experimentally.

We propose a stochastic model for signals generated through the electron multiplying effect of detectors in charged particle beam equipments. This model is based on a stochastic variable characterized by a log-normal type distribution. The model is simple and can be used to represent a wide dynamic range of signals from pulse-like signals when the primary beam current is small to continuous signals when the primary beam current is large. For the model base reference a normalization of actual signal detectors is presented. This base reference yields the unique stochastic parameter used in our model. The proposed model better approximates the actual signals in the power spectrum distribution as compared to the filtered Poisson method presented elsewhere.

We developed a process to fabricate optical functions such as, lens, prism, or diffuser directly on to a glass substrate. Processes include precision mastering by diamond cutting, and multi-layer photopolymer (2P) molding process to realize flat surface and integration of multiple functions with a good alignment within few micrometers.

This paper presents a low-power implementation scheme of interpolation FIR filters using distributed arithmetic (DA). The key idea of the proposed scheme involves look-up tables generating only nonnegative values. Thus, the proposed scheme can minimize the dynamic power consumption of interpolation FIR filters using DA without additional hardware. When used for implementing a pulse shaping filter for CDMA2000 mobile stations, the proposed filter not only has almost the same hardware complexity as the conventional one; it also has approximately 43% reduced power consumption.

26 GHz bandpass filter and duplexer using TM11δ rectangular-mode dielectric cavity resonators are proposed. These have a configuration compact and suitable for mounting on circuit boards. The resonators consisting of the Ba(Mg,Ta)O3 ceramic material showed a high quality factor value of 2600, which is roughly comparable to that of conventional E-plane waveguide filters. The dielectric losses of the ceramic material were experimentally evaluated from the viewpoint of the high frequency operation and the dielectric loss tangent of 7.410-5 was observed at 20 GHz. A three-stage Tchebyscheff bandpass filter with 0.4% relative bandwidth was fabricated and the passband insertion loss was 1.7 dB. A duplexer designed with two TM11δ mode filters and a microstrip T-junction is also presented.