Need to focus already opened window

[sivaranjani]

I have more links. If I click a link from home page, it should open in a new tab. If i click another link from home page, it should open in already opened tab and should be focussed.

[WolfShade]

Use the same variable name for the new tab/window.

var newWin = window.open('document.html',WindowName,'{put settings here}');
newWin.focus();