  Today's communication systems typically use high resolution analog-to-digital
converters (ADCs). However, considering future communication systems with data
rates in the order of 100Gbit/s the ADC power consumption becomes a major
factor due to the high sampling rates. A promising alternative are receivers
based on 1-bit quantization and oversampling w.r.t. the signal bandwidth. Such
an approach requires a redesign of modulation, receiver synchronization, and
demapping. A zero crossing modulation is a natural choice as the information
needs to be carried in the zero crossing time instants. The present paper
provides an overview on zero crossing modulation, achievable rates, sequence
mapping and demapping, 1-bit based channel parameter estimation, and continuous
phase modulation as an alternative zero crossing modulation scheme.
