Google Inc is gearing up to make a serious run at buying wireless spectrum in a Federal Communications Commission auction in January, the Wall Street Journal reported Friday in its online edition.

The company is also prepared to bid on its own without any partners, the Journal said, citing people familiar with the matter. The newspaper said Google is working out a plan to finance its bid -- which could run to $4.6 billion or higher -- that would rely on its own cash and possibly some borrowed money.

No one at Google was immediately available to comment.

Google is running a test version of an advanced wireless network at its Mountain View, California headquarters, gaining operating experience that could come in handy if it wins the spectrum and decides to run a full-scale national mobile carrier, the newspaper said, citing people familiar with the matter.

(Reporting by Justin Grant; Editing by Louise Ireland)