We investigated the interactions between flicker thresholds and luminance pedestals using threshold versus contrast (TvC) and method of constant stimuli paradigms. High amplitude luminance pedestals were found to elevate flicker thresholds, but low amplitude luminance pedestals were unable to reduce flicker thresholds. Luminance pedestals elevated flicker thresholds more at low temporal frequen...

The interferometric technique allows close-to-the-carrier measurements of both phase and amplitude noise, improving the instrument noise floor by 10–25 dB as compared to the traditional method based on a saturated mixer. Principles and basic equations describing the noise measurement system are given, together with design strategies suitable to microwave and very high frequency bands. Two proto...

In this paper a low-power low-phase-noise voltage-controlled-oscillator (VCO) has been designed and, fabricated in 0.25μm SiGe BiCMOS process. The resonator of the VCO is implemented with on-chip MIM capacitors and a single aluminum bondwire. A tail current filter is realized to suppress flicker noise up-conversion. The measured phase noise is −126.6 dBc/Hz at 1 MHz offset from a 7.8 GHz carrie...

We have investigated noise characteristics of novel GaN/Al0:15Ga0:85N doped channel heterostructure field effect transistors designed for high-power density applications. The measurements were carried out for various gate bias VGS and the drain voltage VDS varying from the linear to the saturation regions of operation VDS > 5 V. Our results show that flicker, e.g., 1=f noise, is the dominant li...

PURPOSE Visual flicker induces a response in human optic nerve blood flow (F(onh)) and inner retinal activity, as assessed by laser Doppler flowmetry and electroretinogram (ERG), respectively. In this study the relationship was examined between the flicker-evoked changes in F(onh) (RF(onh)) and ERG when various parameters of the stimulus were varied. METHODS In five normal observers (mean age...

We aimed to noninvasively estimate the relative contribution of the cone photoreceptors to the photopic flicker electroretinogram (ERG) in humans. Responses to ganzfeld square-wave flicker (15, 30, and 60 Hz) were recorded in the presence of a rod-saturating background. We used a modified paired flash technique in which a bright probe flash was presented at different times during a flicker cycl...

PURPOSE Pikachurin is an extracellular matrix-like protein located in the synaptic cleft of photoreceptors. Pikachurin null mutant (Pika-/-) mice have abnormal ON bipolar cell function. This study aimed to determine the contribution of the ON bipolar cell pathway (ON pathway) of Pika-/- mice to the flicker ERG response and, using vector analysis, identify how the contribution varies with the st...

We describe the statistical properties of light rays propagating though a random sea of gravity waves and compare with the case for scalar metric perturbations from density inhomogeneities. For scalar fluctuations the deflection angle grows as the square-root of the path length D in the manner of a random walk, and the rms displacement of a ray from the unperturbed trajectory grows as D. For gr...

This paper presents a noise reduction technique using common-mode feedback in active CMOS mixers. The proposed decreases the noise, thus reducing common-to-differential conversion arising from mismatch and process variations. In addition, reduces sensitivity to process, voltage, temperature (PVT) variations due negative feedback. A theory is adopted analyze low-noise performance of technique. t...