A 2-bit adaptive sigma delta modulation system that inherently eliminates the idle tones present in conventional and other adaptive sigma delta systems is described. The system incorporates both memory and look-ahead instantaneous step-size estimations and, as shown by computer simulation results apart from eliminating the unwanted idle tones despite dithering, it offers improved SNR performanc...

A new application of sigma-delta modulation has emerged in soft switching three phase power electronic converters. For this application, a conventional sigma-delta modulator with scalar signals and binary quantizer is generalized to a sigma-delta modulator with vector signals and a truncated hexagonal lattice quantizer. This vector sigma-delta modulator has an interesting output spectrum which ...

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This work proposes a novel structure for adaptive sigma delta modulation that leads to considerable improvement in the dynamic range of the modulator. The quantizer step-size is adapted based on estimates of the input signal to the quantizer block rather than on estimates of the input signal to the modulator itself, as is common in current schemes. The proposed structure can be implemented rath...

This paper concerns fine analytical error estimates in analog-to-digital conversion of bandlimited functions using the method of sigma-delta modulation (also called Σ∆ quantization). This method has found widespread usage in practice due to several advantages in its implementation compared to conventional methods (see [1, 11]). A recent mathematical treatment of this problem appears in [3]. Bel...

One of the greatest unsolved problems in the theory of sigma delta modulation concerns the ability to analytically derive the stability, or boundedness, of a high order sigma delta modulator (SDM). In this work, we describe the existing literature and try to clarify the issues involved. We fully derive the stability of first order sigma delta modulators, and derive some important results for th...

High-speed broadband digital communication net­ works rely on digital multiplexing technology where clock synchro­ nization, including processing, transmission, and recovery of the clock, is the critical technique. This paper interprets the process of clock synchronization in multiplexing systems as quantizing and coding the information of clock synchronization, interprets clock justification a...

This paper proposes a feed-forward control in a halfbridge resonant dc link inverter. The configuration of feed-forward control is based on synchronous sigma-delta modulation and the halfbridge resonant dc link inverter consists of two inductors, one capacitor and two power switches. The simulation results show the proposed technique can reject non-ideal dc bus improving the total harmonic dist...

Sigma-Delta modulation techniques have been applied to narrow-band passband signals [Jantzi93]. Recent technology improvement has allowed conversion of GSM channels [Ong97] and DECT channels[Bazarjiani97]. In this report, the main concept behind BandPass Sigma-Delta conversion is briefly explained together with its advantages and applications. The architecture choices for this design are then d...

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