President Carter called yesterday for steady and sustained growth in defense spending over the next several years and said he will propose a $157 billion military budget to Congress next year.

In a speech to the Business Council at the White House, the president committed his administration to an average 4 1/2 percent annual increase in defense spending above the yearly inflation rate during the next five years.

Carter said he was making the commitment to counteract a 20-year military buildup by the Soviet Union and to equip the United States to deal with "the continued turbulence and upheavel" that will mark the 1980s.

"In the dangerous and uncertain world of today, the keystone to our national security is still military strength -- strength that is clearly recognized by Americans, by our allies and by any potential adversary," he said.

Pentagon officials said the defnese budget for the fiscal year that begins next Oct. 1 will call for actual spending of $142 billion, a 3.5 percent "real increase" (above the inflation rate) over the current fiscal year's spending level of $127.4 billion. The $157 billion in defense spending authorization that Carter will propose is about a 5 percent increase in the authorization level, they said.

However, these levels could go much higher depending on the inflation rate, and administration officials made clear that the president is willing to spend whatever it takes to meet his target of increasing the defense budget by an average of 4 1/2 percent a year.

The Carter proposals include continued improvements in U.S. nuclear forces through deployment of the MX missile and other measures; modernization of conventional forces, particularly the Navy, and the creation of fleets of ships and cargo planes for the rapid deployment of U.S. forces anywhere in the world.

The president's call for consistently higher levels of military spending over the next several years marked the culmination of the administration's changing approach by one senior administration official "the end of the Vietnam complex that has so beset American attitudes on defense matters."

In 1976, campaigning for the presidency, Carter promised to cut defense spending by $5 billion to $7 billion. He never achieved this, although White House aides insisted that the promise was kept becasue military spending was held below the levels projected by the Ford administration.

But yesterday, a senior White House official conceded that the president has changed his thinking on how much the United States should spend on the military, in part because his earlier "very high hopes" for reaching significant new arms control agreements with the Soviet Union have not been met.

Carter reiterated his support for arms control yesterday, concluding his speech with a call for Senate approval of the SALT II pact, which he said would prevent the Soviets from "widening any advantage they may achieve in the early 1980s" in strategic nuclear weapons.

Moreover, the higher defense spending levels the president proposed yesterday were in part an effort to satisfy a number of senators who are demanding a larger military budget as their price for voting for the strategic arms limitation treaty.

But even with the reiteration of his commitment to arms control, Carter made clear yesterday that he with carry a much more pro-military banner into the 1980 presidential campaign than he did four years ago.

With the uniformed Joint Chiefs of Staff listening from front-row seats in the East Room, the president referred to the Vietnam war, which he said had shaken but not destroyed the "national consensus . . . around the concept of an active role for America in preserving peace and security for ourselves and for others."

"We have learned the mistake of military intervention in the internal affairs of another country when our own vital security interests were not directly involved." he said."But we must understand that not every instance of the firm application of power is a potential Vietnam."

White House officials said the speech was not a reaction to the crisis in Iran. But Carter referred briefly to the Iranian situation, calling it "a vivid reminder of the need for a strong and united America."

The president cited two major reasons for increasing defense spending. The first, he said, is that "for nearly 20 years the Soviet Union has been increasing its real defense spending by 3 or 4 percent each year" while U.S. military expenditures actually were declining because of inflation. "This," he said, "is creating a real challenge to American leadership and influence in the world."

And secondly, Carter warned that "the 1980s are likely to bring continued turbulence and upheaval."

"As in the past, when the winds of change threaten to arouse storms of conflict, we must be prepared to join our friends and allies in resisting threats to stability and peace," he said.

The president said much of his program will take more than five years to complete, and called for a long-term commitment to the goals he set.

"I am asking for consistent support, steadfast support, not just for 1980 or 1981, but until these commitments have been fulfilled," he said.