Savioja and Välimäki (2000) propose both deinterpolation and frequency warping techniques to reduce dispersion error.
Deinterpolation or point-spreading is used to implement equal unit-delay lengths for propagation in all directions. In this way, the dispersion error is made relatively uniform in all directions.
Once the dispersion is made relatively uniform in all direction, Savioja and Välimäki (2000) use an FIR warping filter with unit delays replaced by first-order allpass sections to either pre- or post-process the mesh signal and further correct dispersion errors. This technique is only applicable in non-realtime situations.