Ok, I have solved it and if someone needs, I am sharing the solution.
in a.aspx page,
<script>
function refreshParentPage() {
$('#form1').submit();
}
</script>
and in my popup page, b.aspx,
<script>
function refreshParent() {
parent.refreshParentPage();
}
</script>
That is all, after that, you can assign this function to any controls onclick event.