  The design of the analog demodulator for receivers with low-resolution
analog-to-digital converters (ADC) is investigated. For infinite ADC
resolution, demodulation to baseband with M = 2 orthogonal sinusoidal functions
(quadrature demodulation) is an optimum design choice. For receive systems
which are restricted to ADC with low amplitude resolution we show here that
this classical demodulation approach is suboptimal. To this end we analyze the
theoretical channel parameter estimation performance based on a simple
pessimistic characterization of the Fisher information measure when forming M >
2 analog demodulation channels prior to an ADC with 1-bit amplitude resolution.
In order to emphasize that this inside is also true for communication problems,
we provide an additional discussion on the behavior of the Shannon information
measure under overdemodulation and 1-bit quantization.
