Japan's Softbank Corp. unveiled 13 new cell phone models on Thursday to compete with bigger rivals when a rule change in October lets mobile phone users keep their phone numbers if they switch carriers.

The new models include three made by Sharp Corp. and two by South Korea's Samsung Electronics. Other makers are Nokia Oyj, Toshiba Corp., NEC Corp. and Matsushita Electric Industrial Co..

The Japanese Internet conglomerate is trying to revive the mobile phone unit it bought from Vodafone Group Plc earlier this year for about $15 billion. The wireless unit has a 16 percent market share, lagging behind rivals NTT DoCoMo Inc. and KDDI Corp.

Softbank also said it would roll out an upgraded version of a high-speed network called HSDPA by mid-October. The network allows downloads of data such as music and video about 10 times faster than on its existing third-generation (3G) network.

We want to completely overturn the image that Vodafone had a weak network and bulky handsets, Softbank President Masayoshi Son told a news conference.

Son said no other carrier has offered 13 models with 54 different color variations for the year-end season.

President Masao Nakamura of DoCoMo, the country's biggest carrier, said at a news conference on Thursday that it plans to introduce 20 phones by next March. He did not specify how many models will be sold before the end of the calendar year.

In August, KDDI unveiled 12 new phones, some of which it began selling in mid-September.

Japanese carriers are making more phones than in previous years because of mobile number portability, a change taking effect on October 24 that will for the first time enable Japanese users keep their phone numbers when they change service providers.