Channel Estimation is a major problem encountered by receiver designers for wireless communications systems. The fading channels encountered by the system are usually time variant for a mobile receiver. Besides, the frequency response of the channel is frequency selective for urban environments where the delay spread is quite large compared to the symbol duration. Estimating the channel is esse...

It is well established that passive frequency standards operated in pulsed mode may suffer a degradation of their frequency stability due to the frequency (FM) noise of the Local Oscillator (LO). In continuously operated frequency standards, it has been shown that a similar degradation of the frequency stability may arise, depending on the used modulation-demodulation scheme. In this paper, we ...

Effective feature extraction for robust speech recognition is a widely addressed topic and currently there is much effort to invoke non-stationary signal models instead of quasi-stationary signal models leading to standard features such as LPC or MFCC. Joint amplitude modulation and frequency modulation (AM-FM) is a classical non-parametric approach to nonstationary signal modeling and recently...

Vocal tremor is defined as slow modulation of fundamental frequency or its amplitude [1, 2]. Even though vocal tremor may be attributed to neurological diseases, it may also be a natural stochastic modulation of voice. Many studies try to measure these modulations assuming that they are stationary. Hence, their analysis is limited to small intervals loosing important information about vocal tre...

The deceptively simple problem of a single inverted reflection in ordinary frequency modulated (FM) radio is considered. It will be shown that this problem has been overlooked in the literature and causes major breakdown in reception. The problem is known as suppressed-carrier AM-FM (SCAM-FM) and is totally destructive to the received signal. We examine the theory and practical measurements of ...

Frequency modulation (FM) is a basic constituent of vocalisation in many animals as well humans. In human speech, short rising and falling FM-sweeps around 50 ms duration, called formant transitions, characterise individual speech sounds. There are two representations FM the ascending auditory pathway: spectral representation, holding instantaneous frequency stimuli; sweep consisting neurons th...

Frequency modulation (FM) is an acoustic feature of nearly all complex sounds. Directional FM sweeps are especially pervasive in speech, music, animal vocalizations, and other natural sounds. Although the existence of FM-selective cells in the auditory cortex of animals has been documented, evidence in humans remains equivocal. Here we used multivariate pattern analysis to identify cortical sel...

The purpose of this study was to reveal the cause of frequency modulation (FM) present in microembolic Doppler ultrasound signals. This novel explanation should help the development of sensitive microembolus discrimination techniques. We suggest that the frequency modulation detected is caused by the ultrasonic radiation force (URF) acting directly on microemboli. The frequency modulation and t...

This article reviews recent progress in Japan in the techniques and applications of dynamic mode atomic force microscopy (AFM), specifically focusing on three topics: (1) mechanical discrimination of intermixed two-atom species and their manipulation by frequency modulation (FM) AFM under ultrahigh vacuum; (2) sub-molecular and atomic-resolution imaging in liquids by FM-AFM; and (3) high-speed ...

Adults show great variation in their auditory skills, such as being able to discriminate between foreign speech-sounds. Previous research has demonstrated that structural features of auditory cortex can predict auditory abilities; here we are interested in the maturation of 2-Hz frequency-modulation (FM) detection, a task thought to tap into mechanisms underlying language abilities. We hypothes...