problem of using remote desktop to connect wireless network

I have a notebook, which have a wireless network card and an ordinary
network
card as well. I say the former card A, and the latter B.

The setting for A follows the direction by ITS. The IP setting for B is
10.0.0.1.

I use B to connect this notebook( we call it N ) with another desk
computer's( we call it D ) network card C, which is set to 10.0.0.2.

After all these setting, N's wireless connection is doing well and it
can
share files with D through B and C. D also can share file with N.

When D use windows' remote desktop connection to reach N by IP
10.0.0.1, it
performs well as if I'm using N. However, after a while N's wireless
connection will be disconnected, and can't be repaired. But if I log
out from
N, the wireless connection will recover.

I don't know why this happens, and how to deal with this problem. Your
any
suggestion will be appreciated.