A woman who helped a spy transmit U.S. military secrets to the Chinese government was sentenced to a year and a half in prison Friday, a reduced term that a judge said was warranted because the woman was controlled by the man she assisted.

Yu Xin Kang, 33, a Chinese national, was a mistress to convicted spy Tai Shen Kuo, a New Orleans furniture salesman. She pleaded guilty in May to aiding and abetting Kuo in his espionage efforts on behalf of the Communist government in Beijing.

Kang was a go-between for Kuo, helping him get secret information about U.S.-Taiwanese military relations to a handler affiliated with the Chinese military.

Prosecutors had sought 30 months in prison, which is at the low end of federal sentencing guidelines.

But U.S. District Judge Leonie Brinkema ordered her to serve 18 months, partly because the judge concluded that Kuo domineered Kang.

"But for Mr. Kuo you would never have been involved in this," said Brinkema. "She was under the control of this man ... I likened him to be a puppeteer."

Federal public defender Michael Nachmanoff said Kang had depended on Kuo since coming to the U.S. at age 19.

"This is a uniquely tragic case," he said. "This is a woman who her entire adult life has been inextricably wound up with Mr. Kuo. She has been financially dependent on him, emotionally dependent on him."

Court papers indicate that Kuo received about $50,000 from Beijing for his efforts, much of which he used to support Kang.

Kang tearfully apologized during the sentencing hearing.

"It was all because of my relationship with Mr. Kuo," she said.

Prosecutors acknowledged in court papers that Kang was "a minor participant" who didn't fully understand that she was transmitting U.S. military secrets.

The government has said it has not completely assessed how much damage Kuo's spying had done. But Brinkema said based on classified papers she has read, the damage appears minimal.

Between March 2007 and February, Kuo obtained secrets on U.S. military sales to Taiwan and updates on Taiwan's new air defense system. The Pentagon analyst who handed over the documents mistakenly thought Kuo was affiliated with the Taiwanese defense ministry when in reality he was working for the People's Republic of China.

The analyst, Gregg W. Bergersen, had been sentenced to nearly five years in prison. Kuo is scheduled to be sentenced next week. Guidelines call for him to receive between 16 and 20 years.

The case is one of more than a dozen in the last few years involving either traditional spying or economic espionage related to China. U.S. officials have warned in the last year of increasing espionage efforts by Beijing.