Rezwan Ferdaus, 27, of Ashland, Mass., had been charged with planning to hit the Pentagon and the U.S. Capitol with explosives-packed model airplanes and to rig mobile telephones to set off improvised explosive devices to kill U.S. troops.
Ferdaus pleaded guilty July 20 to attempting to damage and destroy a federal building by means of explosives and attempting to provide material support to terrorists, the Federal Bureau of Investigation said on its website.
U.S. District Judge Richard Stearns also sentenced him to 10 years of supervised release to follow his incarceration.
Ferdaus was arrested last year after the FBI set up an undercover operation.
The FBI said in exchange for his guilty plea, the government dismissed the remaining charges against Ferdaus after the imposition of his sentence. Stearns was quoted as saying the evidence against the accused was overwhelming.
"His actions were self-initiated, deliberate and dangerous. He intended to unleash horrific acts of violence against the people of the United States both here and abroad," First Assistant U.S. Attorney Jack Pirozzolo said.
The Boston Globe reported Ferdaus, who had been planning his jihad for three years, has a physics degree from Boston's Northeastern University. Other reports said he is of Bangladeshi descent.
The FBI said in January 2011 Ferdaus began designing detonation components for explosive devices using mobile phones and supplied 12 such phones to FBI undercover agents he believed were al-Qaida members to be used to kill U.S. soldiers overseas.
After the undercover employees falsely told him one such phone device helped kill three U.S. soldiers in Iraq, Ferdaus said: "That was exactly what I wanted" and that he was "100 percent" at "peace" that his devices "are killing American soldiers," the report said.
Ferdaus also made a 20-minute training video, recorded by the undercover employees, giving instructions on how to make mobile phone detonators, which he believed would be used for training al-Qaida members.
The FBI said Ferdaus also planned to obtain a remote-controlled plane similar to a drone, pack it with grenades and fly it into federal buildings using a built-in GPS device. He had stated his plan "ought to terrorize ... it ought to result in the downfall of this entire disgusting place. That is my goal."
Throughout the undercover operation, Ferdaus had repeatedly reaffirmed his hope to cause mass destruction and psychological harm to the United States, the FBI said.