How to approach Nellis Air base?

When trying to approach Nellis Air Base in Fallout New Vegas, One has to dodge the artillery. The hint you get is to hide behind some high buildings in the northwest (I think). Anyway, there are no high buildings to be seen and I receive the same damage wether I'm near a wall or in the open, I never manage to reach the base.

What's the trick?

I've always done this by hugging the rock ridge on the left side as you approach the base. Most of the rockets will land on the ridge above you, keeping you safe. Once you're close to the fence, the firing stops, and you can follow the fence to the gate and meet Raquel.

If you do take a direct hit, in non-hardcore mode you can just hit the Pip-Boy and use a few stimpaks to restore your health. (This assumes you're high enough level to survive a hit - leveling up before approaching the base is recommended.) Don't neglect your legs - if they get crippled, make sure you use a stimpak on them to keep your movement speed from slowing to a crawl.

The notes section of the Nellis Air Force Base article on the Fallout Wikia lists a few alternative strategies, should mine just not work out for you.