SAO PAULO, Oct 26 (Reuters) - Brazilian telecom firm TIM SA will on Wednesday submit proposals to participate in the country"s auction of 5G mobile spectrum, its senior managers said on Tuesday. On an earning conference call, Chief Executive Pietro Labriola also said the company planned to invest 2.2 billion reais ($390.04 million) more than it had estimated in its original plan for 2022, excluding outlays for the 5G auction. TIM SA had released a guidance report in February saying its capital expenditure during the 2021-2023 period was expected to reach 13 billion reais, including 4.4 billion reais this year. Labriola did not disclose how much TIM SA planned to invest in the 5G auction.Brazil"s government has said it expects to raise around 10 billion reais from the auction scheduled for Nov. 4, based on the minimum bids allowed. read more TIM"s board approved the company"s participation in the auction in September. The Brazilian firm, which is part of Italy"s Telecom Italia (TLIT.MI), reported late on Monday net earnings of 474 million reais in the third quarter, up 21.4% from a year earlier and slightly above market expectations. Shares in TIM SA were down about 2.2% at 11.70 reais in early afternoon trading, while the broader Bovespa index (.BVSP) fell 1.7%. ($1 = 5.6404 reais)