Check out this site for links to manufacturers and their websites (especially for those not so mainstream labels).
http://www.satellite-heaven.de/index.htm?jump=Receiver/
For your question, it seems Citizen are rebadged boxes from a korean manufacturer called AMT
http://www.amt.co.kr/. This is quite common for Far East manufacturers. Many of the 'no-name' are simply rebadged for different markets. It could be that your box is not called the CI2200 on their website, but if you check out the features and the look of the boxes, you'll probably find it.