If you look at the names list on Sephardim.com, you will find 4 numbers behind the name Alcala.Each one of these books are a reference which intern has references.(29) for example contains a list of Jewish names so identified by the Holy Office of the Catholic Church.
If you will look at the heraldry page you will find one of the Alcala references will provide origin information.
Still more.Take a look at the links page.The first link you find will be entitled, "The origin of your name."Place your name in the search field and a response willl come up.
Still one more.There is an outstanding forum on the site.Join the more than 120 members who also seek answers.Someone may be able to assist you and you may be able to assist others.