Tate was part of the team that won the K4 gold medal at the London Games and his out-of-competition samples, provided in Hungary on July 21-22 last year, tested positive for the steroid stanozolol.
The 33-year-old had appealed to the Court of Arbitration for Sport, which handed down a two-year ban, the Australian Olympic Committee said in a statement.
Paralympic ace Henshaw hungry for medals ahead of tilt at Tokyo canoeing glory
Smith's ban has been backdated to the day he was provisionally suspended and he will be ineligible to compete until Sept. 8, 2016.
'Excited' Heath claims canoeing European Champs silver
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