The frequency shift of a shear-horizontal surface-acoustic-wave (SH-SAW) biosensor in which the concentration of biomolecule is determined by the amount of its adsorption on the sensing film was studied. Simulation results were compared with experimental results to investigate its sensitivity and to develop a model to estimate the concentration of a cancer-related biomarker antigen epidermal growth factor (EGF) in the sample, with two types of sensing films, 3-aminopropyltriethoxysilane (APTES) and glutaraldehyde. With the concentration of the targeted biomarker varying from 0.2 to 5 ng/mL, a typical exponential relationship was found between the concentration and the frequency shift of the SH-SAW sensor. Measurement results showed a clear response of this immunosensor to the mass-loading effects of the antibody–antigen. The sensitivity of the glutaraldehyde film is greater than that of the APTES film owing to the chemisorption of the antibody. In the simulation, a shift of the SH-SAW resonant frequency due to added mass occurred on applying an incremental surface mass density on the sensing film, while in real applications, the concentration of the targeted biomarker to be absorbed in the sensing film is demanded. An empirical model was proposed to calculate the frequency shift in the simulation of the SH-SAW biosensor, corresponding to the concentration of specific biomolecules absorbed on a specific film. From the semi-empirical model, the sensitivity level is found to be 0.641 and 1.709 kHz/(ng/mL) for APTES and glutaraldehyde sensing films, respectively, at a biomarker concentration of less than 1 ng/mL. The developed method is useful for quickly estimating the frequency shift with respect to the concentration of the target molecules in the simulation for SH-SAW sensors.

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This paper presents an impIantabIe integrated FM transmitter using 0.35um SiGe process for biotelemetry. The architecture of FM transmitter is based on the Colpitts oscillator, which is followed by a buffer amplifier to isolate the influence of output on the resonant frequency of the oscillator. The chip area of the fabricated FM transmitter is only 0.26 mm' . Even wlthout an intentional antenna, the experimental results show that electrocardiograms (ECGs) of a rat using the FM transmitter can be successfully transmitted to a personal computer, where the heart rate variability is analyzed. I. INTRODUCTIONRecently, as the development of system-on-chip (SoC) technologies advances, there has been a growing interest in implantable wireless biotelemetry for diagnosis [1]-[5], Many of them are based on de

A narrowband active noise control (NANC) structure is often applied to reduce undesired noise when multiple tones have close frequencies. A parallel ANC structure is proposed for separating undesired harmonics into a series of adaptive filters. Since the input signal of each adaptive filter has only one harmonic component, a second-order finite impulse response (FIR) filter is sufficient for processing the undesired noise. Therefore, the presented parallel structure for NANC system is greatly simplified. Based on the input signal frequency, a bank of bandpass filters splits the frequency components of the error signal to update the corresponding adaptive filters in the parallel NANC structure, each of which is computationally very simple and unaffected by time delay. A new performance index for a parallel NANC is also proposed. The increased convergence speed obtained by the proposed method is first confirmed by theoretical analysis. Computer simulations are then performed to confirm the enhancement.