wireless reception goes in and out

[LSUfan1853]

i bought my macbook about a month ago, i also have a dell laptop as well. my wireless reception on the mac goes from 4 bars to 1 continuously and its VERY frustrating. it does not do this on my dell laptop AT ALL. what gives? my router is literally 30 feet (at most) from both of my laptops that are in the same room. it is a linksys router. what could be the problem here and what are the resolutions?