Proceq GS8000 comes with a rugged cart and can work on most surfaces without a problem. If the wheels can move, then your antenna can collect subsurface data. However, you must keep in mind that very uneven surfaces can create some pseudo-targets that can be corrected with a GPS.

You must also be aware that moving over conductive materials, e.g., aluminum, copper etc. can limit or even zero the penetration depth of your radar antenna.