Wideband Communication System Sensitivity to Overloading Quantization Noise

The performance of analog-to-digital converters (ADCs) is usually characterized in their granular region, by adopting amplitude-limited sine-wave testing signals. However, some applications, like digital telecommunication systems, often require the conversion of signals which noticeably differ from sine-waves and which may introduce ADC overloading phenomena. In this paper, the uniform A/D conversion of Gaussian signals is investigated, assuming both memoryless and sigma-delta (Σ-Δ) converters. Then, the effects of quantization noise upon the behavior of a digital communication system (DCS) are considered. By extending previously published results, a model is introduced, which describes the bit error rate performance of an orthogonal frequency division multiplexing system also in the presence of overloading quantization noise, both for memoryless and Σ-Δ A/D uniform converters. Such a model allows a relation of the ADC requirements to the DCS ones.