This depends on the soil conditions, and most importantly on the dielectric and the electrical conductivity. The higher the water and salt content...

This depends on the soil conditions, and most importantly on the dielectric and the electrical conductivity. The higher the water and salt content in a material, the shallower a radar penetrates the ground.

Pulsed systems face the frequency dilemma on top of the soil dielectric/conductivity. Users must select a specific frequency, and this adds an extra limitation to the max depth penetration. The higher the frequency the shallower you penetrate, but the better the resolution you get. On the other hand, the lower the frequency the deeper you penetrate, but the resolution gets worse. Stepped Frequency Continuous Wave (SFCW) systems do not face this frequency dilemma.