The Soviet Union has adopted a two-pronged public relations strategy leading up to the Geneva summit meeting, increasing anti-U.S. rhetoric at home to lower expectations, while abroad it is avoiding direct confrontation with the Reagan administration and appealing to critics of U.S. arms control positions, according to western analysts here.

The shift in Soviet public statements to American and international audiences from confrontation to defensiveness is aimed at greater adeptness in appealing to critics in the United States and among U.S. allies of Reagan administration policies such as the "Star Wars" missile defense plan, the analysts said.

Soviet Foreign Minister Eduard Shevardnadze's speech yesterday at the United Nations, critical of the United States but short on virulently anti-American rhetoric, exemplifies the face lift in Moscow's treatment of the United States in the international arena, analysts here said.

"We have never been the initiators of confrontation between the United States and the Soviet Union," Shevardnadze told the U.N. General Assembly.

In contrast, the Soviet Communist Party newspaper Pravda and other Soviet publications aimed at domestic rather than international audiences have sharpened their criticism of the United States in recent weeks. The Soviet press has featured frequent attacks on the Reagan administration's arms control positions and heavy coverage of some American human rights cases.

"Prior to previous summits with the Americans, the anti-U.S. rhetoric has been calmed in the press," one Soviet commentator said in an interview. "This time it has increased."

The Gorbachev adviser behind the critical treatment of the United States in the Soviet press is Aleksander Yakovlev, U.S. Kremlinologist Jerry Hough said in an interview here. Yakovlev, a former Soviet ambassador to Canada, has written several harshly anti-American works, including most recently, "From Truman to Reagan."

Shortly after summit plans were announced last July, Soviet officials shifted from confronting the Reagan administration on arms control to appealing to critics of Reagan's Strategic Defense Initiative (SDI), the space-based antimissile project popularly known as "Star Wars." Criticism of the United States before domestic audiences picked up at the same time.

"They want to give the world the impression that they are approaching the summit reasonably," one senior western diplomat here said of senior Soviet officials, "and they are dampening expectations at home for positive results there."

Before the announcement of the summit conference, Soviet leader Mikhail Gorbachev warned that if the U.S. negotiators continued "marking time" at the Geneva talks, the Soviet Union would have to "reappraise the entire situation" -- apparently threatening a walk-out.

More recently, Gorbachev has dropped his confrontational tone and adopted the language of western peace activists, backing it up with reminders of his moratoriam proposals on nuclear testings and deployment of intermediate-range missiles.

"We can either survive or perish together," Gorbachev said in an interview with Time magazine Aug. 28. "We are prepared to switch our mode . . . to a peaceful track. As you say, live and let live."

Other Soviet officials, too, have launched appeals to opponents of the U.S. position in Geneva, particularly of SDI. Georgi Arbatov, head of the U.S.A. and Canada Institute, recently returned to Moscow from a trip to the United States, where he met with SDI critics. In recent weeks, Gorbachev has conferred in Moscow with opposition politicians from Japan and West Germany who have pledged their opposition to the program. He is to go next week to France, the strongest critic of SDI in Western Europe.

Despite Reagan's persistent position that Star Wars is not a bargaining chip in the Geneva talks, Gorbachev raised his June offer of "really deep cuts" in Soviet nuclear armaments, to an August promise of "radical proposals" for arms reductions as a trade-off for SDI. Soviet officials have leaked rumors that Shevardnadze will tell Reagan that "radical proposals" refers to a 40 percent cut.

In the Soviet press, articles accusing the United States of "whipping up the arms race" and poisoning the atmosphere before the summit meeting persist.

In addition there have been heavily publicized examples of U.S. abuses of human rights, which western observers say have picked up since the summit was announced.

The Soviet Union's attempt to enlist other countries in its opposition to SDI suits the aims of Gorbachev's professed preference for a broader foreign policy that would deemphasize relations with Washington, western analysts here said. "The intention of the policy is to get other countries to put pressure on the U.S. before the summit," a senior western diplomat said.

Since Gorbachev came to power in March, Moscow has put a greater emphasis on improving its relations with China and Japan, countries that have enjoyed positive political relations with the United States. After the TWA hostage crisis in June, the Soviets engaged in a flurry of diplomatic initiatives in the Middle East.

"They have tried to make use of every opportunity to broaden their narrowly concentrated influence in throughout the Middle East," the diplomat said.