Analog frequency modulated (FM) systems offer advantages of reliable speech quality and simplicity, whereas code division multiple access (CDMA) systems promise high capacity, resistance to multipath fading, and simplified frequency planning. In this thesis, we investigate the performance of a wireless local loop (WLL) system that uses the frequency modulation with the CDMA technique. The perfo...

In this paper, the potential sensitivity in Kelvin probe force microscopy (KPFM) was investigated in frequency modulation (FM) and heterodyne amplitude modulation (AM) modes. We showed theoretically that the minimum detectable contact potential difference (CPD) in FM-KPFM is higher than in heterodyne AM-KPFM. We experimentally confirmed that the signal-to-noise ratio in FM-KPFM is lower than th...

Jamming of radar guided missile receivers are extremely difficult as the frequency lock and the servo lock requires no deviations in the repeater waveform of the jammer and its frequency. Broadband repeat jamming of such missile radar receiver is illustrated in this paper for effective deception in the presence of FM CW (Continuous Wave) interference signal. The modulation index of the FM jamme...

I always had difficulties in understanding frequency modulation (FM) and its frequency spectrum. Even for the pure tone modulation, the FM spectrum consists of an infinite number of sidebands whose signs change from one sideband to the next one and whose amplitudes are given by the horrible Bessel functions. . . I work for Zurich Instruments, a Swiss maker of lock-in amplifiers and it has becom...

Fibromyalgia (FM) has been associated with cardiac autonomic abnormalities and pain. Heart rate variability (HRV) is reduced in FM with autonomic tone dominated by sympathetic activity. The purpose of this study was to evaluate the effects of one session of a posteroanterior glide technique on both autonomic modulation and pain in woman with FM. This was a controlled trial with immediate follow...

Conventionally, digital halftoning is accomplished by either changing the size of printed dots or changing the relative density of dots on the page. These two approaches are analogous to amplitude modulation (AM) or frequency modulation (FM) used in communications. A typical AM halftoning method, such as cluster dot screening, has very low computational requirements and good print stability. Ho...

The objective of this research is to propose a video/audio system which allows the user to listen the typical music notes in the concert program under infrared detection. The system synthesizes audio with different pitches and tempi in accordance with the encoded data in a 2-D barcode embedded in the infrared watermark. The digital halftoning technique has been used to fabricate the infrared wa...

In this paper, we suggested new algorithms to discriminate between eight analogue modulated signals (amplitude modulation (AM), frequency modulation (FM), double side band (DSB), lower side band (LSB), upper side band (USB), vestigial side band (VSB), combined (AM-FM) and carrier wave (CW)). The simulation results show that the overall recognition of the new algorithms over 97% when the signal ...

Communication is the method by which two persons can share any meaningful information with each other at an instant. It requires a sender who wants to communicate, message which is to be conveyed & receiver who receives this message at the receiver end. Now a days due to the advancements and technology, digital communication is receiving wide attention among researchers. Digital communication i...

In this paper, we investigate the advantages of frequency modulation (FM) features by conducting speech recognition experiments and statistical analysis. The importance of temporal aspects in speech recognition has been discussed along with the importance of amplitude modulation (AM) and frequency modulation. Recently, we have proposed a speech recognition system that is based on the combinatio...