Coherent state quantization of angle, time, and more irregular functions   and distributions
  The domain of application of quantization methods is traditionally restricted to smooth classical observables. We show that the coherent states or "anti-Wick" quantization enables us to construct fairly reasonable quantum versions of irregular observables living on the classical phase space, such as the angle function, the time function of a free particle and even a large set of distributions comprising the tempered distributions. 
Biswajit Chakraborty, Jean Pierre Gazeau, Ahmed Youssef