Officials in the State Department and the Pentagon's Strategic Defense Initiative Office have concluded that Soviet-sought limitations on President Reagan's "Star Wars" missile defense program would interfere with only a handful of tests of SDI technology out of dozens envisioned between now and 1995, according to administration sources.

Though Reagan has said he will not use SDI as a "bargaining chip" at next month's summit with Soviet leader Mikhail Gorbachev, several officials in his administration, including Adm. William J. Crowe Jr., the chairman of the Joint Chiefs of Staff, think it may be possible to negotiate limits on SDI testing without fatally compromising the program of research on space-based missile defense, the sources said.

Crowe disclosed his view at a secret meeting last month of Reagan's senior arms-control advisers, sources said. At issue was a Soviet proposal to open negotiations on rules that would govern future tests of space-based defenses -- for example, a restriction on the brightness of any laser tested in space to a fraction of the power that would be needed to shoot down a barrage of enemy missiles.

At the White House meeting, Crowe told Reagan that the Soviet proposal was worth serious consideration and should not be "dismissed out-of-hand" after then-Secretary of Defense Caspar W. Weinberger urged its rejection at the same meeting. Although Reagan was not persuaded, Crowe directed his staff to begin studying the Soviet proposal, sources said.

The debate at that meeting was part of a broader disagreement that has dogged the administration since 1983 and is expected to resurface at next month's summit meeting in Washington: Is there a way for the Reagan administration to satisfy Gorbachev's demands for some limits on SDI in return for deep cuts in strategic offensive arms? Reagan has indicated he would like an agreement on such deep cuts to be the crowning achievement of his presidency.

Reagan has signaled in several recent speeches that his answer to Gorbachev's demands for SDI limits remains "no." But Weinberger's resignation on Nov. 21 removed the administration's most vigorous opponent of the idea, causing some administration officials to sense possible winds of change.

Officials said it is unlikely that a new U.S. position will be agreed on before the summit begins Dec. 8. However, several officials said, a new position may be formulated in response to Soviet positions advanced at the summit, whose formal agenda includes discussion of "the observance of and nonwithdrawal from" the 1972 Antiballistic Missile Treaty that bans deployment of space-based missile defenses.

Some White House and State Department officials, including senior arms control adviser Paul H. Nitze, have privately said that recent State and Pentagon studies on the potential impact of the limits the Soviets now seek suggest that the two sides are not as far apart as commonly believed.

The studies found that although the latest Soviet proposal, if accepted, would preclude a few planned SDI tests, dozens could go forward. The State Department study concluded that, nevertheless, the Soviet proposal was flawed because some of the methods it proposes for measuring specific tests were unworkable. The Soviets have said their proposal -- advanced in its latest form in September -- is negotiable.

Nitze has long argued with little success in the administration that a U.S.-Soviet agreement on what kinds of SDI tests would be permissible would solidify congressional support for the program and smooth the path to an accord on long-range arms, while allowing SDI scientists to pursue most if not all of the research that interests them.

But other officials, including new Secretary of Defense Frank C. Carlucci, have insisted that any agreement on research limitations could backfire because of uncertainty about which tests are needed.

"By definition, you don't know what you're going to do in an R&D {research and development} program, and for us to. . . try and negotiate limits with the Soviet Union makes no sense at all," Carlucci said at a news conference Tuesday. "Eventually, it may be constraining."

Carlucci's viewpoint is shared by Arms Control and Disarmament Agency Director Kenneth L. Adelman, who plans to leave office after the Reagan-Gorbachev summit, and by special arms control adviser Edward L. Rowny.

The Soviets, in response to such concerns, have suggested that the two sides simply agree now to follow the "traditional" interpretation of the ABM Treaty, which bars realistic missile defense testing in space.

This is "the major issue," Roald Sagdeev, a senior Soviet scientist, said in a recent news conference in Washington. He added that "one, two {or} three" years from now, the two sides could agree on specific research limitations -- in other words, after the Reagan administration is out of power.

Soviet Foreign Minister Eduard Shevardnadze said after meeting with Secretary of State George P. Shultz in Moscow on Oct. 25 that "we said -- and we are now confirming -- that we allow research and not only research work" on SDI. Prototypes of SDI weapons can also be created in laboratories and test ranges, Shevardnadze said.

This suggestion, capping a series of Soviet shifts toward greater flexibility on SDI, "is exactly the sort of thing that scares the daylights out of the program's hard-core supporters," an administration official said.

By stressing an immediate research constraint no tougher than that imposed by Congress in the defense authorization bill for fiscal year 1988, which effectively limits tests of SDI technologies to those permitted by the traditional interpretation of the ABM Treaty, the Soviets "are trying to make it as hard as possible for the administration to say no," the official explained.

Defense Department officials and congressional supporters of SDI acknowledged concern last week that Gorbachev may come to the Washington summit with a similar missile defense proposal and concessions on long-range arms. The concern is based in part on recent shifts at the top of the Reagan administration that raise questions about the current balance of opinion on SDI. There is uncertainty about the views of Lt. Gen. Colin L. Powell, Carlucci's successor as national security adviser, and William H. Webster, who recently succeeded William J. Casey -- a strong SDI supporter and close friend of the president -- as director of the Central Intelligence Agency.

One official said Weinberger was worried enough about what Reagan might do that he devoted much of the secret White House meeting of senior arms control advisers on Nov. 20 to "a cheerleading session on SDI and a savage attack on the Soviet position." The 20th was Weinberger's second-to-last day as defense secretary.

On the eve of a meeting between Shultz and Shevardnadze several weeks earlier, Weinberger arranged for Reagan to see a pro-SDI film, "SDI-A Prospect for Peace," produced at a cost of $500,000 by the American Defense Preparedness Association, funded in part by SDI contractors.

Reagan responded with a taped message to the association that the film, which draws an analogy between SDI and life-saving research into diseases such as spina bifida, was "worth four stars." (The United States Information Agency plans to distribute it worldwide at government expense, according to the association.)

Weinberger is also credited with arranging, as one of his last achievements in office, a presidential visit on last Tuesday to the Martin Marietta Corp. in Denver, where scientists have begun preparations for an SDI test costing hundreds of millions of dollars that would be blocked by the Soviet Union's current proposal for detailed restrictions on SDI research.

The test, code-named "Zenith Star" and scheduled for the early 1990s, involves shining an orbiting laser onto a large mirror and reflecting it onto a simulated target in space.

The goal is to demonstrate that a laser, one of the technologies traditionally associated with the "Star Wars" program, can be pointed accurately enough to destroy a ballistic missile streaking through space. Critics inside and outside the government have called the test a waste of funds because the laser, which is powered by chemical fuel, cannot readily be made efficient enough to use in a ballistic missile defense.

"The principal motivation for the test seems to be political, not scientific," said John Pike, an SDI critic at the Federation of American Scientists.

As Reagan was shepherded through upbeat briefings in Denver, he was pointedly warned by Frederick Seitz, a member of SDI's scientific advisory group and a strong proponent of deploying defenses, that "testing restrictions are the death-knell of SDI."

Pentagon officials have resisted preparing a U.S. counteroffer to Soviet proposals for SDI testing limits on grounds it will lead inevitably to a U.S.-Soviet compromise placing tighter constraints on SDI research than currently imposed by the disputed "broad" interpretation of the ABM Treaty embraced by the administration in 1985.

"Any research limits that I can imagine living with would surely be unacceptable to the Soviets," one defense official said.

In an effort to block U.S.-Soviet agreement, a group of conservative senators led by Malcolm Wallop (R-Wyo.) recently charged Nitze, in effect, with conducting back-channel negotiations on SDI limits by providing unauthorized instructions to independent experts affiliated with the U.S. National Academy of Sciences who conferred with the Soviets on their latest proposal. The senators, also including Strom Thurmond (R-S.C.), ranking minority member of the Judiciary Committee, asked for an investigation by the Federal Bureau of Investigation, which has not yet responded.

Nitze, the State Department and the National Academy of Sciences denied the allegations, which outraged officials in his office. The senators' effort has had the effect of constraining discussion of the Soviet proposal in the administration, according to senior officials.