iPhone 4 symbols and what they mean

What does the phone receiver over about 5 dots symbol next to the battery in the top right corner mean. And how do you get rid of it. I first noticed it after I lost all my telephone contacts. I am having to readd everyone and am sure I will miss someone. But I went thru the entire restore process and still didn't get them back. No other problems just hate loosing all my stored numbers I have had for years. Help me with this if you can please. Thanks, Txpondgirl