Current radar net coverage calculation has such deficiencies as huge calculation amount, low velocity and low precision.To solve the problems, the radar models of vertical coverage of three frequency bands are built, and the planar coverage model in geodetic coordinates is built by using the longitude incision method.The detection area of the radar net is incised into a couple of strips with the same longitudinal intervals so that a strip-shaped radar net is formed.The planar coverage of each radar in the net is projected onto the strip-shaped radar net.The strip-shaped model of radar net coverage is built, and an incision algorithm is given.A simulation was carried out on the radar net composed of 30 radars.The result shows that the proposed method reduces the two-dimension calculation amount to one dimension, which lowers the calculation amount, improves the velocity, solves the complex problem of masking boundary, acquires a more accurate spherical area, and solves the problem of the calculation of radar net coverage.