Schmidt speaks frequently about the importance of providing people around the world with Internet access and technology.
As Google's chief executive for a decade until 2011, Schmidt oversaw Google's ascent from a small California startup focused on helping computer users search the Internet to a global technology giant. Google now has offices in more than 40 countries, including all three of North Korea's neighbors: Russia, South Korea and China, another country criticized for systematic Internet censorship.
After being accused of complying with China's strict Internet regulations, Google pulled its search business from the world's largest Internet market in 2010 by redirecting traffic from mainland China to Hong Kong.
In April, Schmidt and Jared Cohen, a former U.S. State Department policy and planning adviser who heads Google's New York-based think tank, will publish a book about the Internet's role in shaping society called "The New Digital Age."
Son Jae-kwon, a visiting scholar at Stanford, compared Schmidt to Chung Ju-yung, the late founder of the South Korean conglomerate Hyundai who strode across the DMZ dividing the two Koreas with a pack of cattle in 1998.
But this time, it's computer technology, not cows.
"Internet is the cattle of the 21st century," Son said. "It is what North Korea needs most."
The Richardson-Schmidt trip comes at a delicate time politically. In December, North Korea defiantly shot a satellite into space on the back of a three-stage rocket, a launch Pyongyang has hailed as a major step in its quest for peaceful exploration of space.
Washington and others, however, decry it as a covert test of long-range ballistic missile technology designed to send a nuclear-tipped warhead as far as California. The U.N. Security Council quickly condemned the launch, and is deliberating whether to further punish Pyongyang for violating bans on developing its nuclear and missile programs.
The visit also follows North Korea's announcement that an American citizen has been jailed in Pyongyang on suspicion of committing "hostile" acts against the state. Richardson will try to address his detainment, the sources said.
State Department spokeswoman Nuland said Schmidt and Richardson would be traveling as private citizens and carrying no messages from Washington.
"We don't think the timing of the visit is helpful and they are well aware of our views," she told a news briefing.
Washington and Pyongyang do not have diplomatic relations. North Korea and the U.S. fought on opposite sides of the three-year Korean War before signing a truce in 1953.
However, North Korea has indicated interest in repairing relations with Washington.
In 2011, a group of North Korean economists and diplomats visited Google headquarters in Mountain View, California.
And North Korean-affiliated agencies already use at least one Google product to get state propaganda out to the world: YouTube.
Associated Press writer Matthew Pennington in Washington contributed to this report. Follow AP's bureau chief for Seoul and Pyongyang at twitter.com/newsjean and AP Seoul's technology writer at twitter.com/ykleeAP