Philippine President Corazon Aquino flew home to continuing political uncertainty this afternoon after an upbeat three-day state visit here that won admiration from the Japanese public and promises of more trade and economic aid.

People here received Aquino with a verve they rarely show for their own leaders. Students at Waseda University in Tokyo chanted, "Cory! Cory!" when she received an honorary doctorate there. Business leaders gave her a standing ovation at a luncheon.

Philippine officials described it as a simple get-aquainted visit. But Aquino brought her Cabinet's economic team and spent much of the time in meetings with aid officials and company presidents.

"What we have accomplished in this visit has far exceeded my expectation," she told reporters before boarding a plane today.

Throughout the visit, she and her delegation had only the kindest words for Japan, despite past criticism in her government of Tokyo's cooperation with former president Ferdinand Marcos. Philippine officials have said Japan is key to clearing away economic ruin that it inherited from Marcos and lately have played down allegations of corrupt dealings by Japanese companies with Marcos.

Japan has cooperated by turning back on an aid tap that it shut off in Marcos' final months and accommodating some of Manila's requests on how the aid is given. Philippine Finance Minister Jaime Ongpin yesterday signed papers converting a Marcos-era project loan into a commodity loan.

Some new money has also come through. The major case is a special $ 250 million loan for a coal-fired power plant. The plant is to supply electricity that was to come from a nuclear plant that Aquino has barred from operating because of safety questions.

Japan has promised to consider raising its regular low-interest development loans above the current annual $ 310 million. It has given no word on how much, however. Ongpin said his government is aiming for the $ 470 million to $ 500 million range, but press reports here suggest it will be much lower.

Japan is also discussing making a loan through its export-import bank to accompany a $ 300 million reconstruction loan from the World Bank, but has made no commitment yet on the level.

Aquino met at the Akasaka Palace guest house in Tokyo with presidents and chairmen of the major Japanese trading companies and leaders of the country's large business federations.

Afterward, they issued statements pledging help. But in private, many officials and businessmen remain wary, citing continuing political instability.

"It's too soon to think about investment," said an executive at a major Japanese trading company.

Some companies have promised new investment, however. Others talk of helping the Philippines export more through factories that already exist, a comparatively low-risk way to help recovery.

Aquino's speeches praised Japan's postwar recovery and called for a new era of cooperation.

"There is a lot we can do together," she said at a banquet hosted by Prime Minister Yasuhiro Nakasone.