En fallstudie i huruvida mångfalden av valmöjligheter och funktioner i en modern synth påverkar musikskapandeprocessen. Undersökningen fokuseras på att undersöka hur dagens kompositörer använder sig av ljudskapande i moderna synthar. Syftet med denna undersökning är att se om mångfald av funktioner i en modern synth påverkar musikskapandet, för att ge läsaren en tankeställare angående arbetsflödet i sitt musikskapande, så att en effektivisering av processen kan tillämpas och att om möjligt, ge rum för mera musikskapande och mindre teknikförståelse. Denna undersökning gjordes genom att genomföra ett antal intervjuer samt en kompletterande enkätundersökning. Slutstsen jag kommit fram till är att en mångfald av funktioner påverkar musikskapandet, antingen negativt eller positivt beroende på genre och kompositörens erfarenhet av synthar.

In this proposal, an advanced local oscillator with high resolution, low phase noise and fast switching characteristics is designed for wireless communication applications. The circuit is based on fractional-N frequency synthesis technique in which the use of delta-sigma modulator can remove the fractional spurs effectively. The mechanism in regard to fractional spurs and phase noise for a fractional-N frequency synthesizer will be studied and simulated by developing proper mathematical models. In the implementation of the local oscillator, the analog circuit includes a 1000-1033 MHz VCO, crystal oscillator and loop filter. The digital circuit includes a phase frequency detector, dual modulus divider and 3rd order delta-sigma modulator. At first a FPGA will be used to prototype the digital circuit. The final digital circuit will be implemented in a CMOS process and require 3V operation with low current consumption. The design specifications include that under 1 KHz resolution the phase noise levels are less than -90 dBc/Hz at frequency offets within a loop bandwidth more than 100 KHz. Spurious components are less than -90 dBc/Hz and switching time is less than 1 ms over a 30 MHz tuning range.

An ISM-band frequency synthesizer is introduced in this thesis. The technique allows digital phase/frequency modulation to be achieved in a closed phase locked loop (PLL) without mixers and D/As. According to the simulation results using ADS, quantization noise will be filtered by the PLL bandwidth. But the data rate is also bounded by the PLL bandwidth. Two key components of this closed-loop architecture, Gaussian filter and delta-sigma modulator have been implemented by FPGA together with the Qualcomm Q3236 synthesizer IC.

Thesis (M. Phil.)--University of Hong Kong, 1998. / Includes bibliographical references.

Mitt arbete handlar om hur jag vill förbättra min förmåga att återskapa ljud från referenslåtar, med hjälp av Serum. Därför har jag försökt att återskapa fyra specifika ljud i form av syntet, från fyra redan kända låtar. Som en utmaning valde jag dessutom att bara använda mig av en synthesizer, i form av mjukvara. Jag valde även att gå igenom mitt genomförande i videor som jag själv spelat in, där vi kan följa med och lyssna hur jag har återskapat dessa fyra ljud. Eftersom jag valde att återskapa fyra ljud från grunden, fick jag en bättre förståelse och grund för hur jag i framtiden kan gå till väga för att skapa mina egna ljud, där återskapandet inte bara kretsade runt Serum, utan även runt efterarbetet.

Vocal prosody (pitch, timing, loudness, etc.) and its use to convey emotions are essential components of speech communication between humans. The objective of this dissertation research was to determine the efficacy of using varying vocal prosody in robotic speech to convey emotion. Two pilot studies and two experiments were performed to address the shortcomings of previous HRI research in this area. The pilot studies were used to determine a set of vocal prosody modification values for a female voice model using the MARY speech synthesizer to convey the emotions: anger, fear, happiness, and sadness. Experiment 1 validated that participants perceived these emotions along with a neutral vocal prosody at rates significantly higher than chance. Four of the vocal prosodies (anger, fear, neutral, and sadness) were recognized at rates approaching the recognition rate (60%) of emotions in person to person speech. During Experiment 2 the robot led participants through a creativity test while making statements using one of the validated emotional vocal prosodies. The ratings of the robot’s positive qualities and the creativity scores by the participant group that heard nonnegative vocal prosodies (happiness, neutral) did not significantly differ from the ratings and scores of the participant group that heard the negative vocal prosodies (anger, fear, sadness). Therefore, Experiment 2 failed to show that the use of emotional vocal prosody in a robot’s speech influenced the participants’ appraisal of the robot or the participants’ performance on this specific task. At this time robot designers and programmers should not expect that vocal prosody alone will have a significant impact on the acceptability or the quality of human-robot interactions. Further research is required to show that multi-modal (vocal prosody along with facial expressions, body language, or linguistic content) expressions of emotions by robots will be effective at improving human-robot interactions.

This dissertation presents a 2.4 GHz wideband GFSK-modulated frequency synthesizer using two-point delta-sigma modulation (TPDSM). The two bottlenecks in this design have been rigorously investigated. One bottleneck is the nonlinear performance of the phase-locked loop (PLL). The other one is the inherent gain and delay mismatch between the two modulation points. Both nonlinear and mismatch factors dominate the modulation accuracy in the closed PLL. The proposed formulation can successfully predict the dependencies of the modulation accuracy on both factors. The comparison of the averaged frequency deviation and frequency-shift -keying (FSK) error between theory and measurement shows excellent agreement. The modulated frequency synthesizer implemented in this study can achieve a 2.5 Mbps data rate as well as a 15 £gs PLL stable time with only 2.2 % FSK error under good design and operating conditions.

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / A Phase Modulator combining digital techniques with non-traditional analog circuitry can minimize the shortcomings of a traditional (purely analog) Phase Modulator. These shortcomings are: nonlinear response from input modulating signal to output modulated signal; parameters (frequency and modulation index) that are difficult to set; and the need for complex filters. The design approach discussed in this paper uses a combination of Direct Digital Synthesis (DDS) and analog devices operating in their linear range to generate a Phase Modulated RF (140 MHz) signal. A Numerically Controlled Oscillator (NCO) digitally generates the first IF yielding a very accurate, repeatable and linear signal with easily adjustable parameters such as frequency and modulation index. Linear multipliers (instead of saturated diode mixers or step recovery diodes) are used for up-conversion to RF. Using linear multipliers eases the filtering requirements due to the significantly reduced harmonics and IM (Inter-Modulation) terms. The resulting RF signal is easily translated to higher frequency bands such as L, S, C, X or K.

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Presentation for ITC 98 of Alcatel Espace last studies and developments regarding TTC Products This document lays on 3 parts: · a technical point of view · a technology/design description · a synthesis showing main performance and results

Data conversion is the crucial interface between the real world and digital processing systems. Analogue-to-digital converters and digital-to-analogue converters are two key conversion devices and used as the interface. Up to now, the conventional ADCs based on Nyquist sampling theorem are facing a critical challenge: the resolution and the sampling rate must be radically increased when some applications such as radar detection and ultra-wideband communication emerge. The offset of comparators and the setup time of sample-and-hold circuits, however, limit the resulution and clock rate of ADCs. Alternatively, in some applications such as speech, temperature sensor, etc. signals remain possibly unchanged for prolonged periods with brief bursts of significant activity. If trational ADCs are employed in such circumstances a higher bandwidth is required for transmitting the converted samples. On the other hand, sampling signals with an extremely high clock rate are also required for converting the signals with the feature of sparsity in time domain. The level-crossing sampling scheme (LCSS) is one of the data conversions suitable for converting signals with the sparsity feature and brief bursts of signigicant activity. due to the traditional LCSS with a fixed clock rate being limited in applications a novel irregular data conversion scheme called analogue-to-information system (AIS) is proposed in this thesis. The AIS is typically based upon LCSS, but an adjustable clock generator and a real time data compression scheme are applied to it. As the system-level simulations results of AIS show it can be seen that a data transmission saving rate nearly 30% is achieved for different signals. PLLs with fast pull-in and locking schemes are very important when they are applied in TDMA systems and fequency hopping wireless systems. So a novel triple path nonlinear phase frequency detector (TPNPFD) is also proposed in this thesis. Compared to otherPFDs, the pll-in and locking time in TPNPFD is much shorter. A proper transmission data format can make the recreation of the skipped samples and the reconstruction of the original signal more efficient, i.e. they can be achieved in a minimum number of the received data without increasing much more hardware complexity. So the preliminary data format used for transmitting the converted data from AIS is also given in the final chapter of this thesis for future works.