  A new model for sparse time dispersive channels in pilot aided OFDM systems
is developed by considering prior knowledge on channel time dispersions.
Weighted atomic norm minimization is implemented in the model which enables a
more accurate channel estimation. The channel response is identified by solving
a Least Squares problem. In this work, we assume that time dispersions'
associated frequencies can take any value with a minimum distance on the
normalized interval $[0,1)$. The performance of the new model is compared with
conventional approaches. With respect to pilot number and SNR, the simulation
results reveal that the new model performs superior to that of conventional
methods. It is shown that both a lower energy and pilot number are required to
achieve the same symbol error rate (SER) reported in previous works.
