从http://developer.android.com/reference/android/telephony/TelephonyManager.html#DATA_SUSPENDED上看到下列的话
public static final int DATA_SUSPENDED
Added in API level 1
Data connection state: Suspended. The connection is up, but IP traffic is temporarily unavailable. For example, in a 2G network, data activity may be suspended when a voice call arrives.
Constant Value: 3 (0x00000003)
应该是2G网络有问题, 不知道3G和4G怎么样。